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Polymers in surfactant mesophasesBrooks, Jason Travis January 1992 (has links)
No description available.
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AN APPLICATION OF THE PRINCIPLES OF FLOW THROUGH PARTIALLY SATURATED POROUS MEDIA TO PROBLEMS OF AGGLOMERATED HEAP LEACHING.Kelzieh, Amer, 1959- January 1985 (has links)
No description available.
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Atomistic simulation of solvation thermodynamics and structureMurdock, Stuart Erwin January 2001 (has links)
No description available.
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Electrochemical studies in room temperature ionic liquidsSilvester, Debbie Sue January 2008 (has links)
The work presented in this thesis involves the application of room temperature ionic liquids (RTILs) as solvents for use in electrochemical experiments. Initially, the fundamentals of electrochemistry is presented, followed by a comprehensive overview of RTILs in terms of their properties, applications and their behaviour as electrochemical solvents compared to conventional aprotic solvents. The results of 8 original studies are then presented as follows: X-Ray photoelectron spectroscopy is used to quantify the concentration of bromide ions in an ionic liquid, and is independently confirmed by potential-step chronoamperometry. The reaction mechanisms and kinetics for the electrochemical reduction of some aromatic nitro compounds (namely nitrobenzene and 4-nitrophenol) are determined. The electrochemistry of phosphorus trichloride and phosphorus oxychloride is studied in detail for the first time, due to the unusual stability of these highly reactive compounds in RTILs. The reductions and oxidations of sodium and potassium nitrate are studied, giving rise to 'melt'-like behaviour. The electrodeposition of sodium oxide on platinum is also demonstrated. The electrochemical oxidation of nitrite and the oxidation and reduction of the toxic gas, nitrogen dioxide, is presented. The oxidation of hydrogen gas is studied in ten RTILs with a range of different cations and anions, and contrasting interactions with the RTIL anions are seen. The electrochemical oxidation of ammonia gas is studied in five RTILs with different anions and a general reaction mechanism is suggested. The reduction of benzoic acid is studied in six RTILs, and the kinetics of the dissociation step are found to be very fast. The first five studies are all carried out in one particular ionic liquid, and the reactions and mechanisms are compared to that observed in conventional aprotic solvents. The last three studies employ several RTILs with different cations and anions to look at the contrasting interaction of protons with the RTIL cation/anion and ultimately help to understand the pH properties of the solvent. The overall findings from the work in this thesis are that some reactions and mechanisms (e.g bromide, nitro derivatives and ammonia) are generally the same in RTILs as in conventional aprotic solvents, but other species (e.g. nitrates, phosphorus derivatives) show remarkably different behaviour. It has also been demonstrated that RTILs are suitable media for the detection of nitrogen dioxide, hydrogen and ammonia gases. This suggests that RTILs could potentially offer many advantages when employed as solvents in electrochemical reactions and in amperometric gas sensors.
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Exploring the relationship between context, process and outcome factors associated with a Solution Focused Coaching Programme for school staffEllis, Natasha Louise January 2013 (has links)
Paper one: The use of coaching programmes is on the increase, including within the field of education. However critics have raised concerns regarding the limited research base concerning their use and the fact many models do not appear to be underpinned by a theoretical basis. One psychological approach to coaching used within the education sector are Solution Focused Approaches, with psychologists including Educational Psychologists taking on the role of ‘executive’ coaches. This paper explores the experiences of school staff and executive coaches involved in one such Solution Focused coaching programme delivered within schools. The paper focuses on exploring the impact of and relationship between contextual, process and outcome factors. Key findings included the fact school staff were not always clear about the aims and purpose of the coaching, that factors such as relationship building and increasing coachees’ sense of ownership were central processes within sessions and that measuring the outcomes of the coaching presented a range of challenges. Within the paper the findings are explore in relation to psychological perspectives including Self-determination theory. Paper two:Following the increased popularity and use of coaching approaches, including within the education sector there is evidence that training courses are being marketed to school staff wishing to implement peer coaching programmes ‘in-house’. Educational Psychologists (EPs) are one group of professionals involved in the delivery of such training and in supporting school staff in implementing coaching following training. This paper focused on exploring the experiences of school staff involved in a Solution Focused peer coaching programme, following training from EPs. Particular focus was placed on exploring the impact of and relationship between contextual, process and outcome factors. Key findings included evidence of potential challenges related to schools not commissioning follow up sessions after training and a perception that the peer coaching had resulted in improvements in OFSTED ratings. Implications for practice include the importance of EPs drawing on and sharing research literature regarding factors which may promote or inhibit changing practice and EPs supporting staff in developing outcome measures which can sit within a SF framework.
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A study of the use of brief- solution focused therapy procedure to reduce the alcohol involvement of a young adolescent maleOtoka, Charles 01 May 1998 (has links)
This study examined the effect of the use of Brief-Solution Focused Therapy procedures on a young adolescent male, whose history suggested alcohol involvement on a daily basis. The data given during the baseline, intervention and follow-up phases, were obtained using the index of alcohol involvement scale, developed by Hudson.
The A-B-A single system research design was used to analyze the data in all three phases. The conclusion drawn from the findings suggests that a series of brief –solution focused therapy reduced the alcohol involvement of the young adolescent male. The result of a student t statistic test also showed that there was a statistical significance between the baseline phase and the intervention phase, thereby supporting the conclusion of this study.
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Occurrence and Function of Hoogsteen Base Pairs in Nucleic AcidsZhou, Huiqing January 2016 (has links)
<p>Nucleic acids (DNA and RNA) play essential roles in the central dogma of biology for the storage and transfer of genetic information. The unique chemical and conformational structures of nucleic acids – the double helix composed of complementary Watson-Crick base pairs, provide the structural basis to carry out their biological functions. DNA double helix can dynamically accommodate Watson-Crick and Hoogsteen base-pairing, in which the purine base is flipped by ~180° degrees to adopt syn rather than anti conformation as in Watson-Crick base pairs. There is growing evidence that Hoogsteen base pairs play important roles in DNA replication, recognition, damage or mispair accommodation and repair. Here, we constructed a database for existing Hoogsteen base pairs in DNA duplexes by a structure-based survey from the Protein Data Bank, and structural analyses based on the resulted Hoogsteen structures revealed that Hoogsteen base pairs occur in a wide variety of biological contexts and can induce DNA kinking towards the major groove. As there were documented difficulties in modeling Hoogsteen or Watson-Crick by crystallography, we collaborated with the Richardsons’ lab and identified potential Hoogsteen base pairs that were mis-modeled as Watson-Crick base pairs which suggested that Hoogsteen can be more prevalent than it was thought to be. We developed solution NMR method combined with the site-specific isotope labeling to characterize the formation of, or conformational exchange with Hoogsteen base pairs in large DNA-protein complexes under solution conditions, in the absence of the crystal packing force. We showed that there are enhanced chemical exchange, potentially between Watson-Crick and Hoogsteen, at a sharp kink site in the complex formed by DNA and the Integration Host Factor protein. In stark contrast to B-form DNA, we found that Hoogsteen base pairs are strongly disfavored in A-form RNA duplex. Chemical modifications N1-methyl adenosine and N1-methyl guanosine that block Watson-Crick base-pairing, can be absorbed as Hoogsteen base pairs in DNA, but rather potently destabilized A-form RNA and caused helix melting. The intrinsic instability of Hoogsteen base pairs in A-form RNA endows the N1-methylation as a functioning post-transcriptional modification that was known to facilitate RNA folding, translation and potentially play roles in the epitranscriptome. On the other hand, the dynamic property of DNA that can accommodate Hoogsteen base pairs could be critical to maintaining the genome stability.</p> / Dissertation
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Chirurgie et second invariant de Yamabe / Surgery and the second Yamabe invariantSayed, Safaa El 10 June 2013 (has links)
Le but dans cette thèse est d'expliciter les liens entre les propriétés analytiques, géométriques et topologiques des variétés compactes de dimension n supérieure ou égale à 3 et le comportement des valeurs propres de l'opérateur de Yamabe. On commence par étudier les propriétés de ces valeurs propres : l'un des remarques principales est que leur signe est invariant par un changement conforme de métriques. On s'intéresse plus particulièrement à la deuxième valeur propre de l'opérateur de Yamabe et on fait le lien entre son signe et l'existence des solutions nodales de l'équation de Yamabe. Pour finir, nous donnons une formule de chirurgie pour le second invariant de Yamabe, qui nous permet d'en obtenir une borne inférieure sous certaines hypothèses topologiques / The goal of this thesis is to study the relationships between the analytical, geometrical and topological properties of compact manifolds of dimension n greater or equal to 3 and the behavior of the eigenvalues of the Yamabe operator. We start by studying the properties of these eigenvalues : One of the most important observation is that their sign is a conformal invariant. We are interested particulary by the study of the seconf eigenvalue of the Yamabe operator and we enlight the relations between its sign and the existence of nodal solutions of the Yamabe equation. At last, we etablish a surgery formula for the second Yamabe invariant which allows to obtain a lower bond for the second Yamabe invariant under some topological hypothesis
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Análise do Programa de Bochechos de flúor em escolares da 13ª Delegacia de Ensino da 3ª Divisão Regional de Ensino da Capital do Município de São Paulo / Analysis of the fluoride mouthwash program in schoolchildren of the 13th Delegation of Education of the 3rd Regional Division of Education of the City of São PauloAly, Ilvaita Maria Morais de Carvalho 08 May 1987 (has links)
O objetivo do presente estudo é a avaliação do programa de bochechos de solução de fluor realizada pela Divisão de Estudos, Normas e Programas do Departamento de Assistência ao Escolar da Secretaria de Educação do Estado de São Paulo. A análise consistiu em se observar a atuação do ministrador do bochecho, verificando-se conjuntamente o preparo da solução e o tempo de duração do mesmo, a quantidade da solução e a freqüência do bochecho proporcionado aos escolares, além da incidência de cárie ocorrida desde o início até o final das observações, comparando-a através da aplicação do índice CPOS com a incidência ocorrida com escolares nos quais o bochecho foi rigorosamente controlado. A ausência de prevenção verificada torna evidente que o método não está sendo executado corretamente. / The present study comprehends an evaluation of a program of fluoride solution mouthrinsing application worked out by the Branch of study, Norms and Programmes of the Schoolchild Assistance Division of the Sao Paulo State Department of Education, Brazil. The analysis has comprised the observation of the performance of the persons in charge of the mouthrinsing ministration, taking into account lenght of time spent, the quantity and concentration of solution and frequency of mouthrinsing offered to schoolchildren, besides the incidence of caries occurred since the beginning till the end of the observations, comparing this incidence - through the application of the CPOS index - to trat occurred in school children with whom the mouthrinsing was completely controlled. The absence of prevention observed indicates that the method is not being correctly performed.
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3D Capacitance Extraction With the Method of MomentsLi, Tao 14 January 2010 (has links)
In this thesis, the Method of Moments has been applied to calculate capacitance between two arbitrary 3D metal conductors or a capacitance matrix for a 3D multi-conductor system. Capacitance extraction has found extensive use for systems involving sets of long par- allel transmission lines in multi-dielectric environment as well as integrated circuit package including three-dimensional conductors located on parallel planes. This paper starts by reviewing fundamental aspects of transient electro-magnetics followed by the governing dif- ferential and integral equations to motivate the application of numerical methods as Method of Moments(MoM), Finite Element Method(FEM), etc. Among these numerical tools, the surface-based integral-equation methodology - MoM is ideally suited to address the prob- lem. It leads to a well-conditioned system with reduced size, as compared to volumetric methods. In this dissertation, the MoM Surface Integral Equation (SIE)-based modeling approach is developed to realize electrostatic capacitance extraction for 3D geometry. MAT- LAB is employed to validate its e?ciency and e?ectiveness along with design of a friendly GUI. As a base example, a parallel-plate capacitor is considered. We evaluate the accu- racy of the method by comparison with FEM simulations as well as the corresponding quasi-analytical solution. We apply this method to the parallel-plate square capacitor and demonstrate how far could the undergraduate result 0C = A ? "=d' be from reality. For the completion of the solver, the same method is applied to the calculation of line capacitance for two- and multi-conductor 2D transmission lines.
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