Dissertations / Theses on the topic 'Alternating'
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McCoy, Duncan. "Alternating surgeries." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7396/.
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This thesis is concerned with the question of when the double branched cover of an alternating knot can arise by Dehn surgery on a knot in S^3. We approach this problem using a surgery obstruction, first developed by Greene, which combines Donaldson's Diagonalization Theorem with the $d$-invariants of Ozsvath and Szabo's Heegaard Floer homology. This obstruction shows that if the double branched cover of an alternating knot or link L arises by surgery on S^3, then for any alternating diagram the lattice associated to the Goeritz matrix takes the form of a changemaker lattice. By analyzing the structure of changemaker lattices, we show that the double branched cover of L arises by non-integer surgery on S^3 if and only if L has an alternating diagram which can be obtained by rational tangle replacement on an almost-alternating diagram of the unknot. When one considers half-integer surgery the resulting tangle replacement is simply a crossing change. This allows us to show that an alternating knot has unknotting number one if and only if it has an unknotting crossing in every alternating diagram. These techniques also produce several other interesting results: they have applications to characterizing slopes of torus knots; they produce a new proof for a theorem of Tsukamoto on the structure of almost-alternating diagrams of the unknot; and they provide several bounds on surgeries producing the double branched covers of alternating knots which are direct generalizations of results previously known for lens space surgeries. Here, a rational number p/q is said to be characterizing slope for K in S^3 if the oriented homeomorphism type of the manifold obtained by p/q-surgery on K determines K uniquely. The thesis begins with an exposition of the changemaker surgery obstruction, giving an amalgamation of results due to Gibbons, Greene and the author. It then gives background material on alternating knots and changemaker lattices. The latter part of the thesis is then taken up with the applications of this theory.
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FREIRE, JULIANA ABRANTES. "COUNTING ALTERNATING SIGN MATRICES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6411@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORDurante vinte anos, ficou em aberto uma conjectura de Mills, Robbins e Rumsey para a contagem de Alternating Sign Matrices (Matrizes de Sinais Alternados). Zeilberger demonstrou a validade das fórmulas em meados da década de 90. Esse texto apresenta outra demonstração, atribuída a Kuperberg, que emprega técnicas de física estatística (Gelo Quadrado). São apresentadas também formulações alternativas que fazem uso de produtos tensoriais matriciais.
For twenty years, a conjecture by Mills, Robbins and Rumsey on the counting of Alternating Sign Matrices remained open. Zeilberger proved the formulas in the mid-90`s. This text presents another proof, attributed to Kuperberg, which uses techniques of statistical physics (square ice). Alternative formulations are also shown, making use of matrix tensor products.
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Sorkatti, Layla Hamad Elnil Mugbil. "Nilpotent symplectic alternating algebras." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669034.
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Boys, Clinton. "Alternating quiver Hecke algebras." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12725.
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This thesis consists of a detailed study of alternating quiver Hecke algebras, which are alternating analogues of quiver Hecke algebras as defined by Khovanov-Lauda and Rouquier. The main theorem gives an isomorphism between alternating quiver Hecke algebras and alternating Hecke algebras, as introduced by Mitsuhashi, in the style of Brundan and Kleshchev, provided the quantum characteristic is odd. A proof is obtained by adapting recent methods of Hu and Mathas, which rely on seminormal forms and coefficient systems. A presentation for alternating quiver Hecke algebras by generators and relations, reminiscent of the KLR presentation for Hecke algebras, is also given. Finally, some steps are taken towards discussing the representation theoretic consequences of the results.
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Knight, Vincent. "Alternating sign matrices and polytopes." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54880/.
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This thesis deals with two types of mathematical objects: alternating sign matrices and polytopes. Alternating sign matrices were first defined in 1982 by Mills, Robbins and Rumsey. Since then, alternating sign matrices have led to some very captivating research (with multiple open problems still standing), an outline of which is presented in the opening chapter of this thesis. Convex polytopes are extremely relevant when considering enumerations of certain classes of integer valued matrices. An overview of the relevant properties of convex polytopes is presented, before a connection is made between polytopes and alternating sign matrices: the alternating sign matrix polytope. The vertex set of this new polytope is given, as well as a generalization of standard alternating sign matrices to give higher spin alternating sign matrices. From a result of Ehrhart a result concerning the enumeration of these matrices is obtained, namely, that for fixed size and variable line sum the enumeration is given by a particular polynomial. In Chapter 4, we give results concerning the symmetry classes of the alternating sign matrix polytope and in Chapter 3 we study symmetry classes of the Birkhoff polytope. For this classical polytope we give some new results. In the penultimate chapter, another polytope is defined that is a valid solution set of the transportation problem and for which a particular set of parameters gives the alternating sign matrix polytope. Importantly the transportation polytope is a subset of this new polytope.
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Al-Samak, Basma. "Alternating ring-opened metathesis copolymers." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343280.
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Aiello, Clarice Demarchi. "Qubit dynamics under alternating controls." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93053.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 111-117).
In this thesis, we discuss two problems of quantum dynamics in the presence of alternating controls. Alternating controls arise in many protocols designed to extend the duration over which a qubit is a useful computational resource. This is accomplished by control sequences that either retard decoherence, or that accomplish a quantum operation in as short a time as possible. The first problem tackles the use of a composite-pulse control sequence known as 'rotary-echo' for quantum magnetometry purposes. The sequence consists in the continuous drive of a qubit, with field phases that alternate at specific intervals. We implement such a magnetometry protocol using an electronic qubit in diamond, and experimentally confirm the flexibility yielded by the tuning of sequence parameters that achieves a good compromise between decoherence resilience and sensitivity. The second problem theoretically investigates the time-optimal evolution of a qubit in the case of a restricted control set composed of alternating rotations around two non-parallel axes on the Bloch sphere. Using accessible algebraic methods, we show that experimental parameters, such as the angle between the two rotation axes, restrict the necessary structure of time-optimal sequences. We propose to implement such an evolution through alternate driving as an advantageous alternative to the slow, noisy direct addressing of a nuclear qubit anisotropically hyperfine-coupled to an electronic spin in diamond.
by Clarice Demarchi Aiello.
Ph. D.
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Slanina, Matteo. "Deductive verification of alternating systems /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Rushton, Brian. "Alternating links and subdivision rules /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2815.pdf.
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Rushton, Brian Craig. "Alternating Links and Subdivision Rules." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/1840.
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The study of geometric group theory has suggested several theorems related to subdivision tilings that have a natural hyperbolic structure. However, few examples exist. We construct subdivision tilings for the complement of every nonsingular, prime alternating link and all torus links, and explore some of their properties and applications. Several examples are exhibited with color coding of tiles.
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Johansson, Robert. "Pattern Avoidance in Alternating Sign Matrices." Thesis, Linköping University, Department of Mathematics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7936.
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This thesis is about a generalization of permutation theory. The concept of pattern avoidance in permutation matrices is investigated in a larger class of matrices - the alternating sign matrices. The main result is that the set of alternating sign matrices avoiding the pattern 132, is counted by the large Schröder numbers. An algebraic and a bijective proof is presented. Another class is shown to be counted by every second Fibonacci number. Further research in this new area of combinatorics is discussed.
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Anton, Peter, and André Laschewsky. "Polysoaps via alternating olefin/SO2 copolymers." Universität Potsdam, 1991. http://opus.kobv.de/ubp/volltexte/2008/1721/.
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Contents:
Introduction
Results and discussion
- Monomers studied
- Monomer properties
- Polymerization, copolymer composition and general properties
- Polymer properties in aqueous solution
Conclusion
Experimental part
- Materials
- Copolymerization with S02 (typical procedure)
- Methods
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Belland, Eirik. "Alternating Current Corrosion of Carbon Steel." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16342.
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The objective was to investigate if the established theory concerning corrosion calculations and electrochemical behavior of carbon is valid when steel is exposed to AC in an electrolyte consisting of 3,5 wt% NaCl and distilled water. The experimental work was divided in two main parts. The first part concerned corrosion testing, including weight loss measurements in stagnant conditions in combination with linear polarization resistance experiments. AC-current densities investigated was 0-, 50-, 75-, 100-, 150-, 220- and 500 A/m2. Polarization curves were produced on two weight loss samples, one exposed to 150 A/m2 and the other exposed to 220 A/m2, at the end of the weight loss experiments.From the corrosion testing it was found that the estimated corrosion current densities (icorr) from the weight loss experiments on samples exposed to AC-current densities below 500 A/m2, was in an approximate accordance with the icorr values estimated from LPR. At 500 A/m2 the measured corrosion rates and corresponding corrosion currents were slightly higher than the remainder. The higher corrosion rate measured from the samples exposed to 500 A/m2 is suggested related to a non-faradaic corrosion contribution. The suggested mechanism is a facilitation of grain boundary corrosion at high AC-current densities leading to the loss of grains. This being a non-faradaic corrosion contribution it is not possible to measure with LPR or polarization curves. The constant B [mV] from the Stern-Geary equation was estimated on basis of LPR measurements. The constant displayed a decreasing trend with increasing AC-current densities. This was explained by the lowering of anodic and cathodic tafel slopes with increasing AC-current densities. The polarization resistance (Rp’ - [Ω∙m2]) also showed a decreasing trend with increased AC-current densities. This was explained by the increased current response in the LPR measurements with increasing AC-current densities.The second part was intended to elucidate the effect of AC on electrochemical behavior of the carbon steel through producing polarization curves at different AC-current densities using a rotating electrode experimental setup. Alterations in corrosion current densities, cathodic tafel slopes, limiting current density of oxygen reduction and corrosion potentials on steel without AC and at current densities of 100-, 150-, 220- and 500 A/m2 are investigated during the electrochemical testing.  From the rotating electrode experiments no significant change in corrosion current was found with increasing AC-current densities. The potential range, in which limiting current of oxygen reduction (ilim) appeared, decreased with increasing AC-current densities. This decrease in ilim also affected the corrosion potentials (Ecorr). A decrease in the potential range of ilim leads to a more cathodic Ecorr. A particular observation was found at AC-current densities of 150 A/m2 were the effect of ilim seemed absent. The samples exposed to this AC-current density also attained the most cathodic corrosion potentials at approximately -850mVSCE which was between 200-400mV lower than the samples exposed to the remaining AC-current densities. Cathodic tafel slopes showed a decreasing trend with increasing AC-current density. Anodic rafel slopes were considered absent due to pitting above Ecorr.Pictures of the weight loss samples were captured in the SEM. It was found that the formation of pits occurred on all weight loss samples exposed to AC. On the samples without induced AC no sign of pitting was observed. Hence it was found that the corrosion attacks attained a more local character when AC-current was induced in the steel samples.
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Neshausen, Leanne. "Variability in Extended and Alternating Extinction." The University of Waikato, 2008. http://hdl.handle.net/10289/2228.
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Hens were trained to peck a square stimulus on a touch-sensitive screen under an FR5 reinforcement schedule for a maximum of 30 reinforcers (taking approximately 10 minutes). Then hens experienced extinction sessions of 40 minutes duration. For a total of six conditions, reinforcement and extinction conditions were alternated. Each condition consisted of between approximately 7 and 10 sessions. Results show that structures developed during conditioning remain in extinction, at least for the duration of previous reinforcement sessions. After approximately 10 minutes, behaviour becomes more variable. There was also an absence of any 'extinction burst'. Extended extinction conditions, and alternating extinction conditions with reinforcement conditions had little effect on the variability of behaviour, but did influence the rate of responding. Responding persisted a little longer before gradually declining across sessions in the first extinction condition. In extinction conditions 2 and 3 responding tended to occur more as 'peaks'; short periods of increased responding with periods of non-responding between peaks.
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Sedeh, Mehran Sohrabi. "Water alternating gas (WAG) injection studies." Thesis, Heriot-Watt University, 2001. http://hdl.handle.net/10399/186.
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Wang, Fan. "Alternating direction methods for image recovery." HKBU Institutional Repository, 2012. https://repository.hkbu.edu.hk/etd_ra/1406.
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Leufkens, Kasper Franciscus Hendricus. "Sequential auctions and alternating price competition." Maastricht : Maastricht : Universitaire Pers ; University Library, Universiteit Maastricht [host], 2008. http://arno.unimaas.nl/show.cgi?fid=13358.
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Forthun, Kari. "Alternating Current Corrosion of Aluminium Sacrificial Anodes." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22387.
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Direct Electric Heating (DEH) is applied to subsea oil production and transmission pipelines to prevent freezing of hydrates as wax during productions shut downs. To prevent clogging, the pipes are heated by application of alternating current (AC) voltage. As a result, a risk for AC corrosion is introduced, which is the motivation and subject of this thesis. The steel pipes are coated and applied conventional cathodic protection (CP) by use of AlZnIn sacrificial anodes. The present work focused on the risk of increased rates of AC influenced corrosion of the AlZnIn anodes. Anode samples coupled to steel samples were investigated under applied AC by use of laboratory scale test cells in synthetic seawater at room temperature. In these experiments, which lasted for one week, the applied AC was varied in the range 0.5 to 150 A m-2, and the anode-steel area ratio (AR) was set to either 10:1 or 100:1. Corrosion rates were assessed by weight loss measurements and properties of surface deposits and corroded surfaces were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. For better assessment of anode-steel coupling in practice and the significance of anode-steel area, similar tests were performed by using a connection of two identical pairs of parallel-coupled anode-steel, with area ratio of 100:1. Equipment and methodology for investigation of AC corrosion were developed and evaluated. Results show that the anode corrosion rate increased with increasing applied AC level, while steel is sufficiently protected under the experimental conditions specified above. Anode corrosion rate was influenced both by current provided for the protection of the steel and self-corrosion and the attack was characterized by pit formation and coalescence of these at higher AC levels. High self-corrosion rates were attributed to successive alkalization, explained by hydrogen evolution, and acidification of the anode surface at each AC cycle, which destabilized the protective oxide layer. Corrosion was limited at high AC levels, explained by hydrogen blanketing of the anode surface and by hydrogen trapped within pores of the hydroxide surface film. AC corrosion of the anodes depended strongly on the anode-steel area ratio. In experiments with electrode pair configuration as described above, the significance of the steel samples vanished by increasing the anode-steel area ratio to 100:1. The system functioned as an anode?anode galvanic couple, which caused a significant decrease in the potential of the anodes, giving rise to runaway self-corrosion rates. In experiments with one anode-steel couple, the couple potential also decreased once AC was applied, increasingly in extent with applied AC potential. This further increased the current requirement by increasingly cathodic steel, thereby resulting in extreme anode corrosion at high AC levels in experiments with AR of 10:1. A subsequent positive shift in the couple potential to a stable level lower than the DC operation potential (-1.05 VSCE) of the AlZnIn anode was observed within 20 hours, caused by hydrogen evolution on steel. The time until the positive shift increased with applied AC level and decreased AR. Formation of calcareous deposits on the steel surface under DC conditions is an important aspect of CP in seawater because the deposits reduce the current requirement significantly. Such deposits did not appear to have a similar significance in the presence of applied AC. Increased water reduction by AC, causing pH increase on the steel surface higher than the DC case, reduced the protectiveness of the deposits by inhibition of electrically insulating CaCO3 formation. Preconditioning of the steel surface by CP under usual DC conditions to form the desired deposits did not have a clear influence on the AC corrosion of anodes. The decrease of both the AC and DC components of the cell current as a function of time under moderate applied AC levels, however, indicated the formation of calcareous deposits on steel. No calcareous scales were found to deposit on the anode surface. The decrease of cell current with time can also be attributed to the development of corrosion products on the anode surface. Decrease in the cell current was not appreciable for high AC levels (> 2 V RMS) with an AR of 10:1, explained by the destruction and instability of the calcareous deposits due to vigorous gas evolution. In conclusion, these results suggest that the lifetime of the CP system at high levels of applied AC (V(AC) > 2 V AC or iAC > 30 A m-2) may become significantly reduced in relation to the expected lifetime under DC conditions.
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Lake, Alysia C. I. "Neutron scattering studies of alternating chain antiferromagnets." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360395.
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Jenkins, Mark Daniel. "Synthesis and alternating automata over real time." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:f37ccc5f-8ed6-4b00-b9e3-28c4bb4ec60a.
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Alternating timed automata are a powerful extension of classical Alur-Dill timed automata that are closed under all Boolean operations. They have played a key role, among others, in providing verification algorithms for prominent specification formalisms such as Metric Temporal Logic. Unfortunately, when interpreted over an infinite dense time domain (such as the reals), alternating timed automata have an undecidable language emptiness problem. In this thesis we consider restrictions on this model that restore the decidability of the language emptiness problem. We consider the restricted class of safety alternating timed automata, which can encode a corresponding Safety fragment of Metric Temporal Logic. This thesis connects these two formalisms with insertion channel machines, a model of faulty communication, and demonstrates that the three formalisms are interreducible. We thus prove a non-elementary lower bound for the language emptiness problem for 1-clock safety alternating timed automata and further obtain a new proof of decidability for this problem. Complementing the restriction to safety properties, we consider interpreting the automata over bounded dense time domains. We prove that the time-bounded language emptiness problem is decidable but non-elementary for unrestricted alternating timed automata. The language emptiness problem for alternating timed automata is a special case of a much more general and abstract logical problem: Church's synthesis problem. Given a logical specification S(I,O), Church's problem is to determine whether there exists an operator F that implements the specification in the sense that S(I,F(I)) holds for all inputs I. It is a classical result that the synthesis problem is decidable in the case that the specification and implementation are given in monadic second-order logic over the naturals. We prove that this decidability extends to MSO over the reals with order and furthermore to MSO over every fixed bounded interval of the reals with order and the +1 relation.
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Kupersmidt, Itamar. "Alternating Physically Based Renderingin Low-lit Areas." Thesis, Blekinge Tekniska Högskola, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-16671.
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Background The increase in screen resolution has increased from HD to Ultra-HDduring the last decade. A modern game today with Ultra-HD resolution has overeight million pixels that need to be shaded, combined with the expensive shadingmethod Physically Based Rendering the equations needed to calculate each pixel arenumerous. Objectives This the study aims to remove complexity from the Physically BasedRendering shading method in the form of roughness in low-lit areas. The low-lit areaswill instead be rendered without the roughness attribute. By removing roughnessless calculations will be performed. Methods To remove roughness from low-lit areas the light had to be approximatedusing a diffuse model. The pixel was later converted via Hue Saturation PerceivedBrightness to calculate the brightness. If the pixel was under the given threshold,the pixel was shaded using a low-complexity Physically Based Rendering implemen-tation without roughness. A user study was conducted using Unity game enginewith eight participants being asked to compare different stimuli all rendered withdifferent thresholds for darkness with a reference picture. The aim of the study wasto ascertain if the stimuli without roughness had any perceivable difference from thereference. Results The results of the study show the majority of the participants noticinga difference when comparing the stimuli with the reference. The areas affected wasnot only the low-lit areas but the whole scene. The energy conversion without theroughness value made the whole scene appear darker. Conclusions The roughness value is an integral part of energy conversion andwithout it, the scene will appear much darker. While the majority of participantsnoticed a difference, the lowest threshold resembled the original the most
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Huang, Jing. "Functional Polymers Containing Semi-Rigid Alternating Sequences." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/89884.
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Alternating copolymers represent a special class of copolymers in which the two comonomers copolymerize in a regular alternating sequence along the polymer chain. Of particular interest in our group are the stilbene-maleic anhydride/maleimide alternating copolymers. These copolymers possess sterically congested backbones and precisely placed functional groups arising from the strictly alternating copolymerization. The research in this dissertation is focused on the synthesis, characterization, and potential application of functionalized copolymers that contain semi-rigid alternating copolymer sequences.
The fluorescence properties of a series of non-conjugated, tert-butyl carboxylate functionalized alternating copolymers were investigated. Extraordinarily high fluorescent intensity with excellent linearity was observed for the di-tert-butyl group-containing stilbene and maleic anhydride alternating copolymer in THF. We attributed the origin of the strong fluorescence to the “through space” π – π interactions between the phenyl rings from the stilbene and C=O groups from the anhydride. The fluorescence was maintained when the copolymer was deprotected and hydrolyzed and the resulting carboxylic acid-functionalized copolymer was dissolved in water at neutral pH.
The tert-butyl carboxylate functionalized alternating copolymer sequences were incorporated into highly crosslinked polymer networks using suspension polymerization. After removing the tert-butyl groups by acidic hydrolysis, the surface area of the networks increased significantly. Using this facile two-step strategy, we were able to achieve nanoporous polymers with BET surface area up to 817 m2/g and carboxylic acid-functionalized surfaces. The BET surface area of deprotected polymers increased with increasing crosslinking density, and the stilbene-containing polymers showed systematically higher BET surface area than the styrene-containing polymers due to the stiffness of the alternating sequences. The resulting nanoporous polymers have potential to be employed as solid sorbents for CO2.
The same tert-butyl carboxylate functionalized alternating copolymer sequences were also incorporated into microgels via miniemulsion polymerization. The miniemulsion technique ensured the successful synthesis of microgels with ~100 nm diameter using solid stilbene and maleimide monomers. The resulting tert-butyl carboxylate-containing microgels were converted into carboxylic acid-containing aqueous microgels by acid hydrolysis. These aqueous microgels showed good and reversible lead and copper ion adsorption capacities.
Amine-functionalized nanoporous polymers were synthesized by the post-modification of highly-crosslinked divinylbenzene-maleic anhydride polymers. High amine-contents were achieved by covalently attaching multiamines to the acid-chloride functionalized polymer surface. The resulting polymers showed medium to high BET surface areas (up to 500 m2/g) and high CO2 capture capacities.PHD
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Ratliff, Leah J. "The alternating hecke algebra and its representations." Connect to full text, 2007. http://hdl.handle.net/2123/1698.
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Thesis (Ph. D.)--School of Mathematics and Statistics, Faculty of Science, University of Sydney, 2007.Title from title screen (viewed 13 January 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Mathematics and Statistics, Faculty of Science. Includes bibliographical references. Also available in print form.
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Ratliff, Leah Jane. "The alternating Hecke algebra and its representations." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/1698.
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The alternating Hecke algebra is a q-analogue of the alternating subgroups of the finite Coxeter groups. Mitsuhashi has looked at the representation theory in the cases of the Coxeter groups of type A_n, and B_n, and here we provide a general approach that can be applied to any finite Coxeter group. We give various bases and a generating set for the alternating Hecke algebra. We then use Tits' deformation theorem to prove that, over a large enough field, the alternating Hecke algebra is isomorphic to the group algebra of the corresponding alternating Coxeter group. In particular, there is a bijection between the irreducible representations of the alternating Hecke algebra and the irreducible representations of the alternating subgroup. In chapter 5 we discuss the branching rules from the Iwahori-Hecke algebra to the alternating Hecke algebra and give criteria that determine these for the Iwahori-Hecke algebras of types A_n, B_n and D_n. We then look specifically at the alternating Hecke algebra associated to the symmetric group and calculate the values of the irreducible characters on a set of minimal length conjugacy class representatives.
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Ratliff, Leah Jane. "The alternating Hecke algebra and its representations." University of Sydney, 2007. http://hdl.handle.net/2123/1698.
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Doctor of PhilosophyThe alternating Hecke algebra is a q-analogue of the alternating subgroups of the finite Coxeter groups. Mitsuhashi has looked at the representation theory in the cases of the Coxeter groups of type A_n, and B_n, and here we provide a general approach that can be applied to any finite Coxeter group. We give various bases and a generating set for the alternating Hecke algebra. We then use Tits' deformation theorem to prove that, over a large enough field, the alternating Hecke algebra is isomorphic to the group algebra of the corresponding alternating Coxeter group. In particular, there is a bijection between the irreducible representations of the alternating Hecke algebra and the irreducible representations of the alternating subgroup. In chapter 5 we discuss the branching rules from the Iwahori-Hecke algebra to the alternating Hecke algebra and give criteria that determine these for the Iwahori-Hecke algebras of types A_n, B_n and D_n. We then look specifically at the alternating Hecke algebra associated to the symmetric group and calculate the values of the irreducible characters on a set of minimal length conjugacy class representatives.
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Ahmed, Mustafa M. Abdalla. "Alternating-Current Thin-Film Electroluminescent Device Characterization." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-233432.
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Jádrem této disertační práce bylo studovat optické a elektrické charakteristiky tenkovrstvých elektroluminiscenčních součástek řízených střídavým proudem (ACTFEL) a zejména vliv procesu stárnutí luminiforů na jejich optické a elektrické vlastnosti. Cílem této studie měl být příspěvek ke zvýšení celkové účinnosti luminoforů, vyjádřené pomocí jasu, účinnosti a stability. Vzhledem k tomu, že současnou dominantní technologií plochých obrazovek je LCD, musí se další alternativní technologie plošných displejů porovnávat s LCD. Výhodou ACTFEL displejů proti LCD je lepší rozlišení, větší teplotní rozsah činnosti, větší čtecí úhel, či možnost čtení při mnohem vyšší intenzitě pozadí. Na druhou stranu je jejich nevýhodou vyšší energetická náročnost, problém s odpovídající barevností tří základních barev a podstatně vyšší napětí nutné pro činnost displeje. K dosažení tohoto cíle jsme provedli optická, elektrická a optoelektrická měření ACTFEL struktur a ZnS:Mn luminoforů. Navíc jsme studovali vliv dotování vrstvy pomocí KCl na chování mikrostruktury a na elektroluminiscenční vlastnosti (zejména na jas a světelnou účinnost) ZnS:Mn luminoforů. Provedli jsme i některá, ne zcela obvyklá, měření ACTFEL součástek. Vypočítali jsme i rozptylový poměr nabitých barevných center a simulovali transportní charakteristiky v ACTFEL součástkách. Studovali jsme vliv stárnutí dvou typů ZnS:Mn luminoforů (s vrstvou napařenou či získanou pomocí epitaxe atomových vrstev) monitorováním závislostí svítivost-napětí (L-V), velikost vnitřního náboje - elektrické pole luminoforu (Q-Fp) a kapacitance-napětí (C-V) ve zvolených časových intervalech v průběhu stárnutí. Provedli jsme krátkodobá i dlouhodobá měření a pokusili jsme se i o vizualizaci struktury luminoforu se subvlnovým rozlišením pomocí optického rastrovacího mikroskopu pracujícího v blízkém poli (SNOM). Na praktickém případu zeleného Zn2GeO4:Mn (2% Mn) ACTFEL displeje, pracujícího při 50 Hz, jsme také studovali stabilitu svítivosti pomocí měření závislosti svítivosti na napětí (L-V) a světelné účinnosti na napětí (eta-V). Přitom byl zhodnocen význam těchto charakteristik. Nezanedbatelnou a neoddělitelnou součástí této práce je i její pedagogický aspekt. Předložený text by mohl být využit i jako učebnice pro studenty na mé univerzitě v Lybii.
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Hernández-Morales, José Bernardo. "Electromagnetic stirring with alternating current during electroslag remelting." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28385.
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The electroslag remelting process combines both a chemical refining ability and a better control on solidification which produces materials of more uniform properties. In spite of the advantages of this process, segregation-prone alloys are still difficult to produce via ESR, particularly when large ingot diameters are involved. In this context the study of externally applied electromagnetic fields is of great interest.
An AC operated stirring device was designed and laboratory-scale experiments were conducted. The solidification structures resulting from the stirring as well as the mixing conditions prevailing in the liquid pool were investigated. Also, modelling studies on the electromagnetic body force produced by the stirrer and the resulting thermal field were conducted.
The start of stirring results in a clearly defined band in both steady- and unsteady-state regimes. The microstructure was not significantly modified in the center of the ingot but a loss in directionality was found at the mould wall. It seems apparent that the stirred liquid does not penetrate significantly inside the interdendritic region. Mixing studies revealed that the degree of mixing in the pool is enhanced by the stirring.
The theoretical calculations show that most of the electromagnetic body force is confined to the magnetic skin depth at the mould wall and the metal-slag interface. Using a previously developed two-dimensional heat transfer model it was not possible to reproduce the experimental pool profiles obtained when stirring was applied.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Zhang, Youchun. "Chemical modifications and applications of alternating aliphatic polyketones." [S.l. : [Groningen : s.n.] ; University of Groningen] [Host], 2008. http://irs.ub.rug.nl/ppn/.
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Lukas, Kristen Elizabeth. "The effects of alternating habitats on gorilla behavior." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/30538.
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Cruz, Helena Maria Pires. "Nailed timber joints subjected to alternating load cycles." Thesis, University of Brighton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357016.
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Christie, David W. "Alternating copolymers containing side-chain liquid crystal groups." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311158.
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The copolymerisation of N-ethyl maleimide (NEM) with ethyl vinyl ether (EVE) in benzene (Bz) was investigated. The copolymerisation displays a tendency towards alternation but is not alternating and propagation involves the formation of a 1:1 NEM/EVE charge-transfer complex. This complex and the monomer/solvent complexes were investigated by 1H NMR spectroscopic methods. The equilibria were combined mathematically to model the NEM/EVE/Bz system. The copolymerisations of functionalised N-substituted maleimides, N-4-[6-(4'-methoxy-4-azobenzoxy) hexoxycarbonyl] phenylmaleimide (NMeAz6PM) and N-4-[6-(4'-nitro-4-azobenzoxy)hexoxycarbonyl] phenylmaleimide (NNitAz6PM), with styrene (St), 4-vinyl pyridine (4VP), or EVE as the comonomer were studied and the reactivity ratios calculated. The monomer pairs NMeAz6PM/St, NMeAz6PM/4VP and NNitAz6PM/St produce alternating copolymers but NMeAz6PM/EVE does not. The absence of liquid crystallinity in these materials was attributed to the rigidity of the polymer backbone coupled with the low mesogen content arising from the alternating backbone. Blends of amorphous maleimide based copolymers with 6-(4-methoxy-4'-azobenzoxy)hexanoic acid, 4.2, were investigated. The copolymers chosen were believed to be alternating and are the product of the copolymerisation of N-phenyl, N-(4-methoxy) phenyl, or N-(4-hydroxy) phenyl maleimide with St or 4VP. 4.2 is essentially immiscible with the St based copolymers. However 4.2 is miscible with the 4VP based copolymers and liquid crystallinity is induced. This behaviour is attributed to the formation of hydrogen bonds between 4.2 and the pyridyl units of the copolymer backbone. Blends of 4.2 or 6-(4-nitro-4'azobenzoxy)hexanoic acid, 5.2, with copoly(NMeAz6PM-alt-St) or copoly(NMeAz6PM-alt-4VP) were investigated. The limited miscibility and liquid crystalline behaviour of the acid/styrene copolymer blends was attributed to interactions between the mesogens on the copolymer and the acid. However, the enhanced miscibility and liquid crystalline behaviour seen in the pyridine blends can be attributed to the formation of hydrogen bonds between the acids and the pyridyl units of the backbone, in addition to the acid/copolymer mesogen interactions.
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Khansawai, Paveena. "Chemical modification of alkene-carbon monoxide alternating copolymers." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/12362.
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Reactions of isolated carbonyl groups in ethene/propene-carbon monoxide alternating copolymers were accomplished by acid-catalysed condensation with alkene-1,2-diols (ethane-, propane-, butane- and hexane-1,2-diols) affording alkene-dioxolane copolymers. Oximation with hydroxylamine, O- methylhydroxylamine and O-benzylhydroxylamine resulted in complete conversion of the carbonyl groups to their oxime derivatives. In addition, the conversions of polyketoximes, derived from ethene/propene-carbon monoxide copolymers, to 1-acteoxyiminotrimethylene and 1-benzoxyimino-trimethylene polymers were achieved by treatment with acetic anhydride and benzoyl chloride, respectively. Reaction of 1,4-dione units in ethene/propene-carbon monoxide alternating copolymers has been investigated. Paal-Knorr reactions with aniline, benzylamine and glycine ethyl ester yielded poly(alkenepyrrole) derivatives. The conversion of the carbonyl groups in ethene/propene-carbon monoxide alternating copolymers to methoximes allowed directed a-substitution reactions to be carried out on the polymer backbone. Treatment with n-butyllithium followed by addition of electrophiles (e.g. iodomethane, 1-iodopropane, 1-bromobutane, benzyl bromide and allyl bromide) afforded the polymer products in which 20-38% of the a-syn methylene hydrogens were substituted. The syn selectivity of the lithiation process was established b treatment of the polymethoxime with BuLi/[O-2H]methanol and confirmed by the presence of deuterium signal in the 2H-NMR spectrum corresponding to those observed for the model compounds. Beckmann rearrangement reactions of model compounds [2.5-bis(tosyloxyimino)hexane, 2,5-bis(mesyloxyimino)hexane and 2,5-bis(hydroxyimino)hexane] were investigated and resulted in rearrangement products: N,N'-ethanediyl-bis-acetamide, N-acetyl-b-alaninemonomethylamide and N,N'-dimethylsuccinamide.
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Chavez, Reyes Xavier A. "Electrochemical Disinfection of Municipal Wastewater using Alternating Current." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1907.
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This research focused on chlorine-free disinfection of wastewater by complying with today's regulations. The equipment used was a continuous flow electrochemical reactor connected to an alternating current (AC) power supply. The electrodes used were made out of titanium coated with iridium oxide. To determine the inactivation of Escherichia Coli, a bacterial count method based on the USEPA method 1603 was used.
After several experiments it was determined that electrochemical disinfection using AC was not efficient and economic enough to be classified as a viable alternative to chlorine disinfection. It was demonstrated that chlorine can be produced by electrolysis using AC and that no hydrogen could be noticed as a byproduct of the electrolysis of wastewater. When the results from this investigation were compared to the ones obtained using DC in Acosta (2014), it was determined that the belief that AC and DC are equally efficient at disinfecting wastewater is wrong.
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Ozon, G. A. "Alternating ditransitives in English : a corpus-based study." Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18714/.
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This thesis is a large-scale investigation of ditransitive constructions and their alternants in English. Typically both constructions involve three participants: participant A transfers an element B to participant C. A speaker can linguistically encode this type of situation in one of two ways: by using either a double object construction or a prepositional paraphrase. This study examines this syntactic choice in the British component of the International Corpus of English (ICE-GB), a fully tagged and parsed corpus incorporating both spoken and written English. After a general introduction, chapter 2 reviews the different grammatical treatments of the constructions. Chapter 3 discusses whether indirect objects have to be considered necessary complements or optional adjuncts of the verb. I then examine the tension between rigid classification and authentic (corpus) data in order to demonstrate that the distinction between complements and adjuncts evidences gradient categorisation effects. This study has both a linguistic and a methodological angle. The overall design and methodology employed in this study are discussed in chapter 4. The thesis considers a number of variables that help predict the occurrence of each pattern. The evaluation of the variables, the determination of their significance, and the measurement of their contribution to the model involve reliance on statistical methods (but not statistical software packages). Chapters 5, 6, and 7 review pragmatic factors claimed to influence a speaker’s choice of construction, among them the information status and the syntactic ‘heaviness’ of the constituents involved. The explanatory power and coverage of these factors are experimentally tested independently against the corpus data, in order to highlight several features which only emerge after examining authentic sources. Chapter 8 posits a novel method of bringing these factors together; the resulting model predicts the dative alternation with almost 80% accuracy in ICE-GB. Conclusions are offered in chapter 9.
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Bilgic¸, Huseyin. "Centralisers and normalisers in symmetric and alternating groups." Thesis, University of St Andrews, 1998. http://hdl.handle.net/10023/13507.
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In this thesis, we analyse the structure of the centraliser of an element and of the normaliser of a cyclic subgroup in both Sn and An. We show that the centraliser in Sn of a permutation can be written as a direct product of centralisers of regular permutations and that the centraliser of a regular permutation is a wreath product. In certain cases we prove that this wreath product splits as a direct product and we analyse the centre of the subgroup. We calculate the centraliser of a general permutation in An and show how this is related to the centralisers of regular permutations. We investigate the normaliser of the cyclic subgroup generated by an element of Sn and show how this is related to the centraliser of the permutation. We calculate the centre of the normaliser and investigate when the normaliser splits as a direct product. We carry out a similar investigation for normalisers of cyclic subgroups of An and investigate the relationship between normalisers in An and Sn. We give presentations for both centralisers and normalisers.
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Libman, Benjamin M. "Caffeine’s Effects on Pausing During Alternating Work Requirements." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849709/.
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There is a significant body of literature stating that caffeine is the most widely consumed drug in the world, yet its effects on operant behavior are little understood. Some of the current research on caffeine suggests that it may play a role in altering motivational states related to transitions between previous and upcoming work requirements. The purpose of the current study was to examine the effects of caffeine on postreinforcement pausing during transitions between small and large fixed ratio rudiments. Eight rats were exposed to five doses of caffeine and and a two-component multiple schedule. We found that caffeine does systematically alter the length of pausing during transitions between fixed ratio requirements, however the magnitude of the effect may be dependent on the baseline rate of responding.
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Haddix, Frank Furman. "Alternating parallelism and the stabilization of distributed systems /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Salimian, Alireza. "Alternating current electroluminescent properties of zinc sulfide powders." Thesis, University of Greenwich, 2012. http://gala.gre.ac.uk/9154/.
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In order to investigate the alternating current electroluminescent properties of zinc sulfide powders the following experiments were conducted: synthesis of zinc sulfide phosphors (comprised of zinc, sulfur and copper dopant); thermal shocking of phosphor materials (sudden cooling, using liquid nitrogen, of phosphor particles heated up to 500oC) and analysis of their alternating current electroluminescent properties as well as studies of particle crystal structures by synchrotron and conventional X-ray powder diffraction techniques. Inductively coupled plasma mass spectrometry was utilized to investigate the concentration of co-activator atoms within the zinc sulphide crystal lattice. Electroluminescent panels were prepared and the emission properties were evaluated theoretically in order to obtain a mathematical relationship between various parameters involved in the electroluminescent process. Thermal quenching of zinc sulfide phosphor alters its photoluminescent and electroluminescent properties. The dominant wavelength of the material alters from 504 nm to 517 nm. It appears that the blue centres are vulnerable to the thermal quenching procedure carried out as the blue emission deteriorates and the overall blue emission of the material is reduced due to the role that the interstitial Cu+ species play in this mechanism. The interstitial Cu+ is not as stable in its location within the lattice compared to substitutional Cu+ and hence a thermal shock is prone to effect its location or association with the surrounding atoms. The green emission centre, however, appears to be unaffected. Results obtained from layer by layer analysis of the material demonstrate that the surface of the phosphor particles contain most of the copper content (copper to zinc molar ratio of 0.08% in the surface compared to 0.06% at inner levels distributed within the lattice). The location of the outer copper layer may play a key role in the alternating current electroluminescence (ACEL) process; further experiments need to be conducted in order to prove the foregoing hypothesis. Irrespective of the amount of copper impurity (dopnat) initially added to the zinc sulphide precursor, prior to synthesis of the phosphor, during the high temperature firing of the material (above 700˚C) a considerable amount of the copper will be ejected from the lattice and be washed off in the latter steps of the synthesis process (where the newly synthesized phosphor is washed in concentrated ammonia solution); an initial copper content of 1.2% molar ratio is reduced to 0.154%; however, the duration of the high temperature firing is a key factor in the final amount of copper present within the lattice. XRPD experiments of a working ACEL device (i.e., when the AC field is applied across the electroluminescent phosphor) show that the diffraction lines all shift, but remain within the region where broad diffraction intensity is observed for a powder sample (i.e. random orientation). Indeed the sharp diffraction lines are observed to span across each broad diffraction area associated with the sphalerite phase. The panel exhibits a different diffraction pattern when the device is powered in an AC field compared to when it is not exposed to the field. This clearly indicates that the particles possess piezoelectric properties and the electric field causes strain on the crystal lattice. When considering the major drawbacks of ACEL technology, i.e. it’s short life time and degradation characteristics, defining a mathematical model of its emission degradation is a step towards understanding part of the mechanism of the ACEL process. Due to the various number of parameters involved in the phenomenon of electroluminescence (such as particle size, copper content and random distribution of crystal planes) and the fact that emissions arise from certain centres randomly distributed over each phosphor particle, mathematical models are only accurate when they are formulated in relation to the analysis of a particular batch of phosphor sample and used to prepare a particular panel. Hence, no overall mathematical formulation can be produced to measure the emission properties of various ACEL panels produced by different batches of zinc sulfide phosphors. The findings of this research indicate that sample preparation technique which involves addition of raw zinc sulfide to an already copper doped zinc sulfide causes an increase in the occurrence of nano p-n junctions species within the lattice where the cupper locations form the p-type and the n type is formed from the release of some sulfur atoms from zinc sulfide structure during the high temperature firing relative to the conventional phosphor preparation methods. Larger particles have a higher probability of contacting interstitial copper sites during firing and preparation as copper atoms tend to migrate out of the zinc sulfide lattice toward the surface. Hence larger particles (commercial phosphors) demonstrate better emission properties. Thermal quenching affects the interstitial copper sites more than the other luminescent centres formed of substitutional copper sites. Hence the lowered blue emission occurs. Due to the probability of high dispersion of Cu atoms within the ZnS lattice a useful mathematical model cannot easily be developed for an EL panel. EXAFS analysis cannot be fully relied up on in respect of the interstitial copper environment in these phosphors considering that a small fraction of the copper impurity in the phosphor exists at interstitial sites. However, the results from experiments using XANES confirm a change in the electronic configuration of Zn atoms when samples are quenched.
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Banister, Melissa. "Separating Sets for the Alternating and Dihedral Groups." Scholarship @ Claremont, 2004. https://scholarship.claremont.edu/hmc_theses/158.
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This thesis presents the results of an investigation into the representation theory of the alternating and dihedral groups and explores how their irreducible representations can be distinguished with the use of class sums.
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Nguyen, Bryan M. "The Kauffman Bracket and Genus of Alternating Links." CSUSB ScholarWorks, 2016. https://scholarworks.lib.csusb.edu/etd/360.
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Giving a knot, there are three rules to help us finding the Kauffman bracket polynomial. Choosing knot’s orientation, then applying the Seifert algorithm to find the Euler characteristic and genus of its surface. Finally finding the relationship of the Kauffman bracket polynomial and the genus of the alternating links is the main goal of this paper.
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Martínez, Cuéllar José Luis. "Three magnon excitations in alternating quantum spin/bond chains." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq23412.pdf.
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Wusik, Martin Joseph. "The synthesis and characterization of a regularly alternating copolyester." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/8708.
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Ogiso, Tadashi. "Finite element alternating analysis for stiffened fuselage with cracks." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/18992.
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Putzke, Stephan [Verfasser]. "Alternating-gradient focusing of large neutral molecules / Stephan Putzke." Berlin : Freie Universität Berlin, 2012. http://d-nb.info/1030488487/34.
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Goodluck, Olufemi W. (Olufemi Waheed). "Magnetic separation of strongly magnetic particles using alternating field." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65920.
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Lewis, Vernon Geoffrey. "Development and applications of an alternating gradient force magnetometer." Thesis, Bangor University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262528.
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Tojira, Opas. "Single-molecule fluorescence spectroscopy : Implementation of alternating-laser excitation." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531514.
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Mak, Yick-hong Giuseppe, and 麥易康. "Aberration sensitivity reduction of alternating phase-shifting mask inphotolithography." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30721246.
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Li, Yi. "Studies Related to the Alternating Copolymerization of Substituted Stilbenes." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33235.
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Stilbene containing polymers are a group of interesting and versatile polymers. The pendent phenyl ring along the polymer backbone can impart unusual rigidity to the polymer backbone due to steric repulsion. By functionalizing stilbene, a variety of functional groups and ionic groups can be precisely placed along the polymer chain with tunable charge density. Therefore, stilbene containing polymers are potentially rod-like polyelectrolytes with controllable charges and charge density. They are the basis of a novel group of rigid synthetic polyelectrolytes and can be used for furthering our knowledge of rigid polyelectrolytes.A novel series of methyl substituted stilbenes were synthesized and copolymerized with maleic anhydride. A conversion-time study was undertaken to understand the methyl substituent effect on copolymerization rates. Methyl substituted stilbene-maleic anhydride copolymer compositions were determined by quantitative 13C 1D NMR. SEC measurements showed the weight average molecular weights of these copolymers vary from 3 000 to over 1 000 000 g/mol. No glass transition temperature or crystalline melting temperature was observed between 0 oC and 250 oC by DSC. TGA showed that these polymers have 5% weight loss around 290 oC.
Precursors to a polycation and a polyanion based on functionalized stilbenes and maleimides have been prepared: poly(di-t-butyl-(E)-4,4â -stilbenedicarboxylate-co- N-(4-(t-butoxycarbonyl)phenyl)maleimide) and poly(N,N,Nâ ,Nâ -tetraalkyl-4,4â -di- aminostilbenes-co-N-4-(Nâ ,Nâ -dimethylaminophenyl)-maleimide). These copolymer precursors were characterized by 1H NMR, SEC, TGA, and DSC. The 1H NMR spectrum indicated the rigidity of copolymer backbones. SEC measurements showed the weight average molecular weights of these copolymers vary from 5 000 to 11 700 g/mol. No glass transition temperature or crystalline melting temperature was observed between 0 oC and 175 oC by DSC for poly(di-t-butyl-(E)-4,4â -stilbenedicarboxylate-co-N-(4-(t-butoxy- carbonyl)phenyl)maleimide). TGA showed that this polymer has 5% weight loss around 210 oC and 26% weight loss on the first stage of decomposition which corresponds to elimination of t-butyl functional group in the copolymer.
The homopolymerization of EMS-III via free radical polymerization, anionic polymerization and cationic polymerization was attempted. However, no polymer was obtained from any of these polymerization methods. In anionic polymerization, the solution changed to red upon the addition of the initiator sec-bu-Li, indicating the successful addition of the sec-bu-Li to EMS-III. However, the initiated monomer did not propagate to form homopolymer.
Master of Science
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WU, DAN. "LIQUID-CORE CAPSULES VIA INTERFACIAL POLYMERIZATION AND ALTERNATING COPOLYMERIZATION." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179427662.
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