Dissertations / Theses on the topic 'Periodic table of elements'

The periodic table poses a difficulty for both scientific realists and anti-realists. The antirealist has difficulty accounting for the success of the table during a period in chemistry when many theories and concepts changed; the spatial relations of current tables in use do not show fundamental changes from the original tables proposed by Mendeleev. Yet, most versions of scientific realism are based upon the understanding that theories are some collection of written propositions or equations. The table as an image successfully functions very much like a theory: it is an organization of known facts, has been used to make predictions, and is plastic enough to accommodate unforeseen novel facts. Assuming the truth of the representational relations between the table and the world poses interesting issues for the realist. Ian Hacking's entity realism and the structural realism of several philosophers are both possible versions of scientific realism that fail to account for the table. Hacking's version fails in this case because the role of representation is central to understanding the history of the table; structural realism fails because it diminishes to much the role that first order properties have as they relate to the formulation of the second order relationships that comprise the table. Philip Kitcher of Science, Truth, and Democracy leaves himself open to two interpretations about the metaphysics of pluralism. One of these is indefensible; the other is quite well supported by the plurality of successful periodic tables.
Master of Arts

Greater understanding and accurate predictions of structural, thermochemical, and spectroscopic properties of chemical compounds is critical for the advancements of not only basic science, but also in applications needed for the growth and health of the U.S. economy. This dissertation includes new ab initio composite approaches to predict accurate energetics of lanthanide-containing compounds including relativistic effects, and optimization of parameters for semi-empirical methods for transition metals. Studies of properties and energetics of chemical compounds through various computational methods are also the focus of this research, including the C-O bond cleavage of dimethyl ether by transition metal ions, the study of thermochemical and structural properties of small silicon containing compounds with the Multi-Reference correlation consistent Composite Approach, the development of a composite method for heavy element systems, spectroscopic of compounds containing noble gases and metals (ArxZn and ArxAg+ where x = 1, 2), and the effects due to Basis Set Superposition Error (BSSE) on these van der Waals complexes.

A lei periódica é uma ideia central na Química, relevante na educação científica, pois permite explicar e prever diversas propriedades da matéria, sendo que a tabela periódica, que consiste em sua representação gráfica, é considerada um dos ícones fundamentais da ciência. Para o ensino deste tema, textos literários de divulgação científica (TLDC) podem trazer contribuições, pois além de fomentarem o desenvolvimento das competências de leitura e escrita, podem promover uma boa problematização do conhecimento científico com aspectos socioculturais por possibilitarem discutir questões referentes à ciência e à tecnologia e suas relações com outras áreas da cultura, e, por isso, favorecem uma abordagem interdisciplinar. Desta forma, o objetivo deste trabalho é elaborar, aplicar e validar uma sequência didática (SD) para o ensino da lei periódica, a qual foi elaborada utilizando excertos de textos literários de divulgação científica, para assim verificar potencialidades e limitações dos TLDC em contextos de sala de aula de Química. A SD foi desenvolvida fundamentada no Modelo Topológico de Ensino e avaliada mediante o processo de Elaboração, Aplicação e Reelaboração. O resultado da aplicação foi avaliado principalmente de acordo interações discursivas observadas nos registros audiovisuais das aulas, nos quais foram caracterizados episódios de ensino em que ocorreram retextualizações dos TLDC. Nessas retextualizações foi constatado que foi predominante a abordagem comunicativa do tipo interativa de autoridade, o que sugere uma forma específica de adaptação do discurso de divulgação científica à esfera escolar. Além disso, embora tenham sido observadas dificuldades de interpretação de metáforas presentes nos TLDC, o que exigiu um esforço dos professores e alunos para transposição do discurso de divulgação científica para a linguagem científica escolar, também foram observadas reflexões sobre propriedades de elementos químicos, o que sugere uma potencialidade didática dos TLDC.
The periodic law is a central idea in Chemistry and also relevant in scientific education because it allows to explain and predict several properties of matter, and the periodic table, which consists of its graphical representation, is considered one of the fundamental icons of science. For teaching this topic, literary texts of scientific communication (LTSC) have been applied in this research because besides fomenting the development of reading and writing skills, they might promote a good problematization of the scientific knowledge with sociocultural aspects, allowing the discussion of many questions related to science and Technology and their relationships with others areas of culture, as well as promoting an interdisciplinary approach. In this way, the objective of this work is to elaborate, apply and validate a didactic sequence (DS) for the teaching of the periodic law, which was elaborated using excerpts from LTSC, in order to verify the affordances of the LTSC in contexts of Chemistry classroom. DS was developed based on the Topological Model of Teaching and evaluated through the Elaboration, Application and Re-elaboration process. The result of the application was evaluated mainly according to discursive interactions that were observed in the audiovisual records of the classes, from where teaching episodes were characterized in terms of the occurrency of retextualizations of the LTSC. In these retextualizations it was observed that the interactive/authoratative communicative approach has prevailed, which suggests a particular form of adaptating the discourse of public communication of science to the school sphere. In addition, although difficulties were observed in the interpretation of metaphors present in the LTSC, which has required an effort by teachers and students to translate the discourse of public communication of science into scientific school language, reflections on the properties of chemical elements were also observed, which suggests a didactic potentiality of the LTSC.

We consider the finite two-dimensional Ising model on a lattice with periodic boundaryconditions. Kaufman determined the spectrum of the transfer matrix on the finite,periodic lattice, and her derivation was a simplification of Onsager's famous result onsolving the two-dimensional Ising model. We derive and rework Kaufman's resultsby applying representation theory, which give us a more direct approach to computethe spectrum of the transfer matrix. We determine formulas for the spin correlationfunction that depend on the matrix elements of the induced rotation associated withthe spin operator. The representation of the spin matrix elements is obtained byconsidering the spin operator as an intertwining map. We wrap the lattice aroundthe cylinder taking the semi-infinite volume limit. We control the scaling limit of themulti-spin Ising correlations on the cylinder as the temperature approaches the criticaltemperature from below in terms of a Bugrij-Lisovyy conjecture for the spin matrixelements on the finite, periodic lattice. Finally, we compute the matrix representationof the spin operator for temperatures below the critical temperature in the infinite-volume limit in the pure state defined by plus boundary conditions.

Resumen de algunos de los aspectos más destacados del libro de divulgación científica de Sam Kean: “The Dissappearing Spoon and other true tales from the periodic table”. Black Swan: Londres, 2011. 391 páginas. ISBN: 978-0552777506
Summary of some of the most interesting parts of the popular science book by Sam Kean: “The Dissappearing Spoon and other true tales from the periodic table”. Black Swan: Londres, 2011. 391 páginas. ISBN: 978-0552777506

The purpose and focus of this research is to examine a chemistry of education and to build a metacognitive bridge between the two disciplines, chemistry and education, through autobiographical narrative development of a relational periodic table for education. The elements of teaching are integrated using the actual model of the chemical periodic table of elements as a working metaphor to re-understand teaching and education. Through the narrative analysis of the inter-and intra-relationships (the educational chemical reactions), this thesis posits a new understanding of the complex matrical relationships of education and thus expands this relational knowledge toward developing new and better methods for teachers, students and for all investors of education to engage in and experience the chemistry of education.
xiii, 312 leaves ; 28 cm.

Techniques for a posteriori error estimation for finite element approximations of an elliptic partial differential equation are studied.This extends previous work on localized error control in finite element methods for linear elasticity.The methods are then applied to the problem of homogenization of periodic structures. In particular, error estimates for the effective elastic properties are obtained. The usefulness of these estimates is twofold.First, adaptive methods using mesh refinements based on the estimates can be constructed.Secondly, one of the estimates can give reasonable measure of the magnitude ofthe error. Numerical examples of this are given.

This thesis explores Charles Peirce’s reception of Dmitri Mendeleev’s periodic arrangement of the chemical elements, the further impact of chemistry on Peirce’s philosophy, such as his phenomenology and diagrammatic reasoning, and the relations between Peirce's theory of iconicity and Mendeleev's periodic table. It is prompted by the almost complete absence in the literature of any discussion of Peirce’s unpublished chemistry manuscripts and the lack of attention given to the connections between Peirce’s early study of chemistry and his later philosophy. This project seeks to make a contribution to this otherwise neglected area of Peirce scholarship.

Reflectarrays are passive quasi-periodic sub-wavelength antenna arrays designed for discrete reflected phase manipulation at each individual antenna element making up the array. By spatially varying the phase response of the antenna array, reflectarrays allow a planar surface to impress a non-planar phasefront upon re-radiation. Such devices have become commonplace at radio frequencies. In this dissertation, they are demonstrated in the infrared for the first time--at frequencies as high as 194 THz. Relevant aspects of computational electromagnetic modeling are explored, to yield design procedures optimized for these high frequencies. Modeling is also utilized to demonstrate the phase response of a generalized metallic patch resonator in terms of its dependence on element dimensions, surrounding materials, angle of incidence, and frequency. The impact of realistic dispersion of the real and imaginary parts of the metallic permittivity on the magnitude and bandwidth of the resonance behavior is thoroughly investigated. Several single-phase reflectarrays are fabricated and measurement techniques are developed for evaluating these surfaces. In all of these cases, there is excellent agreement between the computational model results and the measured device characteristics. With accurate modeling and measurement, it is possible to proceed to explore some specific device architectures appropriate for focusing reflectarrays, including binary-phase and phase-incremental approaches. Image quality aspects of these focusing reflectarrays are considered from geometrical and chromatic-aberration perspectives. The dissertation concludes by briefly considering two additional analogous devices--the transmitarray for tailoring transmissive phase response, and the emitarray for angular control of thermally emitted radiation.
Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering PhD

The development of sensor-based technologies has opened up avenues for a dialogue between the body and digital spaces, uncovering new possibilities for cross-disciplinary projects and engagements that demand new methods compatible with the ethos of embodied practices, which, in turn, require new approaches and tools. This research seeks to address this need by examining the quantifiability and visual properties of embodied emotion through a multi-layered study of human movement and gesture. It is an elaboration of scientific and artistic research methods, intended to answer the following principal question and related sub-questions: How can emotions, expressed via whole-body movement be visually documented and archived as a reference framework to stimulate the use and studies of expressive gesture in digital environments? As a consequence the following sub-questions become relevant for this research: The first, ontological in its nature; what is expressed emotion? And the second, methodological; how can bodily expressed emotions be visualised and quantified? To answer these questions, the research is divided into three parts. Drawing on phenomenological interpretative inquiry and heuristic methodology, whole-body emotive expressions are documented and analysed from multiple perspectives: body, expressiveness, time, space volume and their correlations. The first part contains information related to video data collection and the database design. The second part describes silhouette extractions of whole body emotive expressions and an online survey where the visual perception of visual data is measured. The third part of the research contains visual and quantitative data analysis providing the basis for visualisation of the four archetypal emotions: anger, fear, joy and sadness and their relationships. In this process, a multi-method approach was adopted combining both qualitative and quantitative methods adopted from sociology and cognitive science. The contextual review, where virtual embodiment and interactivity are explored build on the aesthetics of performance within new technology, highlighting the adaptability of the methods used in performance art to the field of game design. The results of this research and contribution to knowledge reside within both the ontological and methodological approaches used within this study. The ontological resides within the development of two reference frameworks: a correlation table defined as the Periodic Table of Movements (PTM) and a PTM database. The PTM database is a synthesis of embodied emotion data derived from multiple visual representations such as colour, shape, space, volume, time and intensity, whereas the relationship between expressions is visualised in the PTM correlation table. Within the context of an educational framework, the database also provides visual concepts of emotion as epistemic objects for analysis and experimentation. It is a starting point for future cross-disciplinary studies and research on emotions in the context of embodiment and digital technology. The novel methodology of this research contributes to a number of fields with new methods and models of enquiry, grounded within a hermeneutical interpretation driven by artistic development. This exploration opens up a holistic approach to future studies and research grounded in a multimodal attitude to knowledge acquisition.

The article solves the riddle of the fine structure constants with the help of the Planck units, derives its physical meaning and shows the consequences.:Abstract Introduction What is the fine structure constant? Consequence from the existence of the fine structure constant.

Acompanha: Guia didático para o ensino de química: O estudo dos elementos químicos e sua identificação na abordagem Ciência, Tecnologia e Sociedade (CTS): perspectivas de uma aprendizagem crítica para a 2.ª série do ensino médio
Esta dissertação teve como objetivo geral desenvolver o estudo dos elementos químicos numa abordagem Ciência, Tecnologia e Sociedade, visando contribuir para a formação conceitual, procedimental e atitudinal mais crítica dos educandos da 2.ª série do ensino médio da Escola de Educação Básica Barão de Antonina, na cidade de Mafra, no estado de Santa Catarina. Os objetivos específicos da pesquisa foram identificar a concepção dos educandos sobre as relações sócias da ciência e da tecnologia, levantar os conhecimentos prévios dos alunos sobre os elementos químicos, desenvolver atividades que promovam o estudo dos elementos químicos numa abordagem Ciência, Tecnologia e Sociedade (CTS), utilizando artigos apresentados e selecionados em Revista de Divulgação Científica (RDC) e apresentar um produto educacional, em nível de Guia Didático, que possa ser disseminado, analisado e utilizado por demais professores da educação básica –ensino médio, na disciplina de Química, como exemplo de prática pedagógica numa abordagem CTS. A abordagem metodológica que norteou este estudo foi a pesquisa qualitativa de natureza interpretativa com observação participante. A técnica de coleta de dados foi centralizada na observação participante, anotações em diário de campo, produções escritas dos alunos, fotografias e filmagens, segmentos esses que foram transcritos. Os dados da pesquisa foram coletados e analisados, inicialmente por meio da verificação das concepções prévias dos vinte e um educandos (21), envoltos no processo, tendo-se em conta a relação à temática apresentada. Esse fator possibilitou o direcionamento das atividades para categorias de análise, as quais foram delimitadas por uma etapa exploratória e uma pesquisa-ação, em que os educandos tiveram a oportunidade de participar de forma ativa, cooperativa, intervindo na construção do estudo, com seus saberes, sugestões e reflexões sobre as relações sociais do conhecimento científico e tecnológico. Assim, foi possível desenvolver o processo de construção coletiva da proposta para o enfoque do tema sugerido, pois como produto final se elaborou um guia didático, no qual constam as atividades desenvolvidas. As principais percepções da pesquisa trazem contribuições para ratificar a essencialidade de implementar ações no ato de ensinar e aprender, de modo a aprimorar práticas docentes no ensino de Química, bem como a continuidade da postura reflexiva acerca da Ciência e da Tecnologia, pelos educadores e educandos, viabilizando uma jornada pedagógica produtiva vinculada à formação do cidadão do século XXI.
This work aimed to develop the study of the chemical elements in an approach Science, Technology and Society, to contribute to the formation conceptual, procedural and attitudinal more critical of the two students. Grade school, School of Basic Education Barão de Antonina in the town of Mafra, the state of Santa Catarina. The specific objectives of the research were to identify the students 'design partners on relations of science and technology, raise the students' prior knowledge about chemicals, develop activities that promote the study of the chemical elements in an approach Science, Technology and Society (CTS ) using articles submitted and selected in Journal of Science Communication (RDC) and introduce an educational product, in terms of Didactic Guide, which can be disseminated, analyzed and used by other teachers of basic education - high school, the discipline of chemistry, as an example of a pedagogical approach CTS. The methodological approach that guided this study was the interpretative nature of qualitative research with participant observation. The technique of data collection was focused on participant observation, field diary notes on, students' written productions, photographs and film footage, these segments were transcribed. The survey data were collected and analyzed, initially by means of verification of previous conceptions of twenty-one students (21), wrapped in the process, taking into account the relationship to the theme presented. This factor allowed the targeting of activities to categories of analysis, which were bounded by an exploratory stage and an action research, in which students had the opportunity to participate in an active, cooperative, intervening in the construction of the study, with their knowledge , suggestions and reflections on the social relations of scientific and technological knowledge. Thus it was possible to develop the process of collective construction of the proposed approach to the theme suggested, because as the final product has a guide to teaching, in which the activities listed. The main perceptions of research contributions bring to ratify the essential actions to implement the act of teaching and learning, in order to improve teaching practices in the teaching of chemistry as well as the continuity of reflexive stance on Science and Technology, for educators and students , enabling a productive educational journey linked to the formation of the citizen of the XXI century.

Afin de réduire le bruit dans les villes, il est nécessaire d’avoir une bonne compréhension de la propagation acoustique en milieu urbain. Il existe aujourd’hui des logiciels commerciaux qui permettent de modéliser des champs acoustiques urbains à des coûts de calcul raisonnables. Toutefois, ces outils sont basés principalement sur des approches énergétiques qui ne contiennent pas d’informations sur la phase. Pour cette raison, elles ne permettent pas la prise en compte d’effets d’interférence (par exemple, des résonances), nous offrant ainsi une description physique limitée du champacoustique. Inversement, des méthodes ondulatoires classiques (FEM, BEM, FDTD) permettent de prendre en compte ces effets. Or, en raison de la discrétisation et de la grande extension du domaine de propagation, leur utilisation est généralement limitée aux très basses fréquences.L’objectif principal de cette thèse est de développer des méthodes ondulatoires performants, dans le domaine fréquentiel et temporel, nous permettant de modéliser la propagation acoustique dans des zones urbaines étendues. L’approche proposée est basée sur une formulation mixte modale–éléments finis. L’idée clé de cette méthode estde considérer la rue comme un guide d’ondes ouvert, dont la base modale est composée de modes de fuite (modes qui rayonnent une partie de leur énergie en se propageant). Cette approche combine une description multimodale du champ acoustique dans la direction longitudinale et un calcul par éléments finis des modes propres transverses.L’approche a été mise en oeuvre précédemment à l’échelle d’une seule rue. Dans cette thèse, nous nous intéressons à l’extension de la méthode à l’échelle du quartier, afin de modéliser la propagation dans des milieux contenant un grand nombre de rues interconnectées. Une version simplifiée dans le domaine temporel, contenant uniquement lemode de propagatif le moins fuyant, est également développée.En nous basant sur ces approches, nous étudions des phénomènes ondulatoires qui peuvent apparaître dans des configurations urbaines particulières. Plus précisément, nous nous intéressons à l’interaction des modes de la rue avec des résonances dans une cour intérieure adjacente, ainsi qu’à la formation de bandes de fréquences interditesdans des réseaux périodiques de rues interconnectées. Le résultat principal de cette étude est que, malgré la forte présence de pertes par radiation dans le milieu, des effets de résonance importants peuvent encore se produire. Les résultats présentés dans ce manuscrit mettent en évidence l’importance d’une approche ondulatoire pour décrirecorrectement des champs acoustiques aux basses fréquences, et ils suggèrent l’usage potentiel de ces phénomènes afin de contrôler la propagation acoustique dans le milieu.Enfin, nous présentons une étude sur l’utilisation de métasurfaces (surfaces contenant un réseau de résonateurs) pour améliorer la performance des murs antibruit. Nous démontrons que, grâce à l’excitation des résonances locales sur la métasurface, il est possible d’obtenir des propriétés non conventionnelles, comme par exemple des angles de réflexion négatifs ou de l’absorption acoustique aux basses fréquences
The improvement of the urban sound environment requires a good understanding of the acoustic propagation in urban areas. Available commercial softwares give the possibility to simulate urban acoustic fields at relatively low computational costs. However, these tools are mainly based on energy methods that do not contain information on the phase. Therefore, these tools are unable to capture interference effects (e.g., resonances), providing a limited physical description of the acoustic field. Conversely, classical wave methods such as FEM, BEM or FDTD give the possibility to model interference effects, but their use is often restricted to very low frequencies due to discretisation and the huge extension of the propagation domain.The main goal of this thesis is to develop efficient wave methods for the acoustic propagation modelling in extended urban areas, both in the frequency and time domain. The proposed approach is based on a coupled modal–finite elements formulation. The key idea is to consider the urban canyon as an open waveguide with a modal basis composedof leaky modes, i.e., modes that radiate part of their energy into the atmosphere as they propagate. The approach combines a multimodal description of the acoustic field in the longitudinal direction and a finite elements computation of the transverseeigenmodes. This coupled approach, which has been successfully implemented at the scale of a single street, is extended in the present manuscript at a larger scale (the neighbourhood scale), in order to model problems arising in propagation domains containing many interconnected streets. A time domain version of the method, containing only the least damped mode, is also proposed.Using these methods, we investigate wave phenomena arising in specific urban configurations, as forbidden frequency bands in periodic networks of interconnected streets, and resonances in inner yards. It is found that, despite the presence of significant radiative losses in the propagation medium, strong interference effects are still observed. Not only this result highlights the relevance of a wave approach to describe accurately urban acoustic fields at low frequencies, but it suggest the potential use of these phenomena to control the acoustic propagation in urban environments.The last part of this dissertation presents a preliminary study on the use of metasurfaces (surfaces decorated with an array of resonators) to improve the performance of noise barriers. It is shown that, exciting resonances in these structures, it is possible to achieve some unconventional behaviours, including negative angles of reflection and low frequency sound absorption

Orientador: Renato Pavanello
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-16T17:42:52Z (GMT). No. of bitstreams: 1 Chang_PauloLeeKungCaetano_M.pdf: 2268901 bytes, checksum: 969b1f62e6eb27512023a9dccd41cac6 (MD5) Previous issue date: 2010
Resumo: Neste trabalho estuda-se a propagação de ondas em meios elásticos periódicos e meios poro-elásticos. Para o estudo da propagação de ondas em meios elásticos periódicos, modelos discretos uni e bidimensionais são gerados - seguindo padrões encontrados na literatura - e simulados para a obtenção da estrutura de banda e da resposta em frequência, com o objetivo de observar-se o fenômeno band gap. Em seguida, estuda-se a propagação de ondas e a absorção em meios poro-elásticos periódicos. As equações diferenciais de movimento acopladas da poro-elasticidade são obtidas da formulação mista (u,p), baseada no modelo de Biot-Allard. A modelagem numérica do problema de propagação de ondas em meios poro-elásticos é feita utilizando-se o método dos elementos finitos. Mostra-se por meio de simulações numéricas como os padrões de periodicidade influenciam na estrutura de banda da matriz elástica do material poro-elástico e no comportamento global da curva de absorção. Finalmente, as principais conclusões são apresentadas e sugestões para trabalhos futuros são propostas
Abstract: In this work, a study of propagation of sound in elastic periodic materials and poroelastic media is made. One and two dimension discreet models are produced - following the literature - for the purpose of studying wave propagation in periodic elastic materials. The band structure and the frequency response of these materials are obtained by simulation of these models with the intention of observing the phenomenon of band gap. The case for periodic porous media is then studied. The wave equations for the poroelastic media are derived from the mixed displacement-pressure formulation based on the Biot-Allard's poroelasticity equations. The numerical solution of the wave propagation in porous media problem is calculated by the finite element method. It is showed how different periodic patterns affect the band structure of the solid phase of the porous materials and its acoustic absorption. Finally, the main conclusions are presented and some suggestions for future work are made
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica

Made available in DSpace on 2014-12-17T15:04:45Z (GMT). No. of bitstreams: 1 LorenaGFB.pdf: 460479 bytes, checksum: aa12e0a9baa8d74666214337a2a8c5f5 (MD5) Previous issue date: 2006-05-19
Nowadays there are many reasons that aim to include people with special necessities, like those with visual deficiency, in the world of work, education, and in the society as a whole. However it is observed that when we talk about schooling inclusion, especially in High School, there is a huge gap between the theory and the practice. The lack of didactic resources, the inadequate installations, unprepared teachers, the families? lack of information, are some of the factors that hinder the process of inclusion. Furthermore, the educators also have to deal with the roughness of the disciplinary contents and, refering to the study of Chemistry, with the use of signals related to this subject?s language. So, the objective of our research is to reflect about the apprehension of this language by the visually handicapped people, and try to contribute with their process of inclusion in the school life. On this perspective we work with the Periodic Table, which constitutes one of the indispensable tools necessary to the Chemistry learning. In order to acomplish it, the way followed by us happened in three passages. Initially, by means of a semistructured interview, we tried to get acquainted with the blind students opinion, who were participating in the research about the Periodic Table used by them throughout High School, as well as the dificulties felt when using it. After getting the answers, the Table was reelaborated to fill those students?necessities. Here, two new Tables were designed, one in Braille which shape is more compacted, and another made with high printed dots, built with sand and glue. On the third moment, the new designed Tables were tested by the students and, by means of a semi-structured interview, we tried to identify if this new resource would solve the problems concerned to the old Table. The students showed that the compacted Tables would facilitate the touch reading of the chemical elements simbols, making it clear and fast. We hope that, with the elaboration of this learning tools we can contribute with one of the elements to favor the effective participation of blind students in Chemistry classes, when studying the Periodic Table
Na atualidade, in?meras s?o as raz?es que visam ? inclus?o de pessoas com necessidades especiais, dentre essas, aquelas com defici?ncia visual, no mundo do trabalho, na educa??o, e na sociedade como um todo. Entretanto, observa-se que em se tratando da inclus?o escolar dessas pessoas, especialmente no Ensino M?dio, h? um enorme distanciamento entre a teoria e a pr?tica. A falta de recursos did?ticos, as instala??es f?sicas inadequadas, o despreparo dos professores, a desinforma??o das fam?lias, s?o alguns dos fatores que emperram o processo de inclus?o. Al?m disso, os educandos deparam-se tamb?m com a aridez dos conte?dos disciplinares e, no caso do estudo da Qu?mica, com a utiliza??o dos signos relativos ? linguagem que ? concernente ? mat?ria. Logo, o objetivo de nossa pesquisa ? refletir sobre a apreens?o dessa linguagem pelas pessoas com defici?ncia visual, com vistas a contribuir para o seu processo de inclus?o escolar. Nessa perspectiva, trabalhamos com a Tabela Peri?dica, que se constitui em uma das ferramentas indispens?veis para apropria??o do conhecimento qu?mico. Para tanto, o percurso metodol?gico adotado foi realizado em tr?s etapas. Inicialmente, por meio de uma entrevista semi-estruturada, procurou-se conhecer a opini?o de alunos cegos, participantes da pesquisa, sobre a Tabela Peri?dica que utilizaram no Ensino M?dio, bem como as dificuldades sentidas no seu manuseio. A partir das respostas obtidas, a tabela foi re-elaborada para atender ?s necessidades destes alunos. Nessa etapa, foram constru?das duas tabelas, uma em Braille cuja forma ? mais compacta, e a outra em alto relevo, confeccionada com areia e cola. Na terceira etapa, as tabelas elaboradas foram submetidas a an?lise dos participantes e por meio de entrevista semi-estruturada procurou-se identificar se esse recurso atendia ?s solicita??es feitas pelos alunos quanto ao manuseio. Os participantes sinalizaram que as tabelas compactas facilitavam a leitura t?ctil dos s?mbolos dos elementos qu?micos de forma mais ?gil e clara. Espera-se que, com a elabora??o dessas ferramentas, possamos contribuir com mais um dos elementos a favorecer a participa??o efetiva de alunos cegos nas aulas de Qu?mica, ao estudar a Tabela Peri?dica

Liquefiable soils are common at ports due to the use of hydraulic fills for construction of waterfront facilities. Liquefaction-induced ground failure can result in permanent ground deformations that can cause loss of foundation support and structural damage. This can lead to substantial repair and/or replacement costs and business interruption losses that can have an adverse effect on the port and the surrounding community. Although numerous soil improvement methods exist for remediating a liquefaction-prone site, many of these methods are poorly suited for developed sites because they could damage existing infrastructure and disrupt port operations. An alternative is to use a passive remediation technique. Treating liquefiable soils with colloidal silica gel via permeation grouting has been shown to resist cyclic deformations and is a candidate to be used as a soil stabilizer in passive mitigation. The small-strain dynamic properties are essential to determine the response to seismic loading. The small-to-intermediate strain shear modulus and damping ratio of loose sand treated with colloidal silica gel was investigated and the influence of colloidal silica concentration was determined. The effect of introducing colloidal silica gel into the pore space in the initial phase of treatment results in a 10% to 12% increase in the small-strain shear modulus, depending on colloidal silica concentration. The modulus reduction curve indicates that treatment does not affect the linear threshold shear strain, however the treated samples reduce at a greater rate than the untreated samples in the intermediate-strain range above 0.01% cyclic shear strain. It was observed that the treated sand has slightly higher damping ratio in the small-strain range; however, at cyclic shear strains around 0.003% the trend reverses and the untreated sand begins to have higher damping ratio. Due to the nature of the colloidal silica gelation process, chemical bonds continue to form with time, thus the effect of aging on the dynamic properties is important. A parametric study was performed to investigate the influence of gel time on the increase in small-strain shear modulus. The effect of aging increases the small-strain shear modulus after gelling by 200 to 300% for the 40-minute-gel time samples with a distance from gelation (time after gelation normalized by gel time) of 1000 to 2000; 700% for the 2-hour-gel time sample with a distance from gelation of 1000; and 200 to 400% for the 20-hour-gel time samples with a distance from gelation of 40 to 100. The treatment of all potentially liquefiable soil at port facilities with colloidal silica would be cost prohibitive. Identifying treatment zones that would reduce the lateral pressure and resulting pile bending moments and displacements caused by liquefaction-induced lateral spreading to prevent foundation damage is an economic alternative. Colloidal silica gel treatment zones of varying size and location were evaluated by subjecting a 3-by-3 pile group in gently sloping liquefiable ground to 1-g shaking table tests. The results are compared to an untreated sample. The use of a colloidal silica treatment zone upslope of the pile group results in reduced maximum bending moments and pile displacements in the downslope row of piles when compared to an untreated sample; the presence of the treatment zone had minimal effect on the other rows of piles within the group.

La théorie d'homogénéisation élastodynamique des matériaux hétérogènes initiée par J.R. Willis il y a environ une trentaine d'années a récemment reçu une très grande attention. D'après cette théorie qui est mathématiquement exacte, la loi constitutive homogénéisée est non locale en espace et en temps ; le tenseur des contraintes dépend non seulement du tenseur des déformations mais aussi de la vitesse ; la quantité du mouvement dépend à la fois de la vitesse et du tenseur des déformations, faisant apparaître en général une masse anisotrope. Ces propriétés constitutives effectives, qui pourraient être surprenantes d'un point de vue mécanique classique, se révèlent en fait très utiles pour la conception de métamatériaux acoustiques et de capes acoustiques. Ce travail de thèse consiste essentiellement à proposer et développer deux méthodes numériques efficaces pour déterminer les propriétés élastodynamiques effectives des matériaux périodiquement hétérogènes. La première méthode relève de la méthode des éléments finis alors que la deuxième méthode est basée sur la transformée de Fourier rapide. Ces deux méthodes sont d'abord élaborées pour une microstructure périodique 3D quelconque et ensuite implantées pour une microstructure périodique 2D quelconque. Les avantages et les inconvénients de chacune de ces deux méthodes sont comparés et discutés. A l'aide des méthodes numériques élaborées, la théorie de Willis est appliquée au calcul élastodynamique sur un milieu infini hétérogène et celui homogénéisé. Les différents cas d'homogénéisabilité et de non-homogénéisabilité sont discutés
The elastodynamic homogenization theory of heterogeneous materials initiated by J.R. Willis about thirty years ago has recently received considerable attention. According to this theory which is mathematically exact, the homogenized constitutive law is non-local in space and time; the stress tensor depends not only on the strain tensor but also on the velocity; the linear momentum depends on both the velocity and the strain tensor, making appear an anisotropic mass tensor in general. These effective constitutive properties, which may be surprising from a classical mechanical point of view, turn out in fact to be very useful for the design of acoustic metamaterials and acoustic cloaks. The present work is essentially to propose and develop two efficient numerical methods for determining the effective elastodynamic properties of periodically heterogeneous materials. The first method belongs to the finite element method while the second method is based on the fast Fourier transform. These two methods are first developed for any 3D periodic microstructure and then implanted for any 2D periodic microstructure. The advantages and disadvantages of each of these two methods are compared and discussed. Using the elaborated numerical methods, the Willis theory is applied to the elastodynamic computation over the infinite heterogeneous medium and the homogenized one. The various cases of homogeneisability and non-homogeneisability are discussed

Ce travail consiste à développer un logiciel métier basé sur la modélisation thermomécanique linéaire de l'échangeur tout en intégrant les techniques d'homogénéisation. Une méthodologie de modélisation de l'échangeur constitué par un empilement de différentes ondes et tôles brasées, est donc adoptée. Cette méthodologie suppose que le comportement global de chaque couche d'ondes et tôles, est encadré par deux comportements limites déterminés par des approches mécanique périodique (HMP) et cinématique périodique (HCP). Ces deux approches sont mises en œuvre pour l’application numérique tout en étudiant le chargement interne global dû à la température et à la pression. Un outil d'homogénéisation (HomPass) est ensuite développé afin de déterminer automatiquement les comportements équivalents à chaque onde et tôle brasées. Cela contribue au développement de l'outil métier final (SiTEME) dédié à l'étude thermomécanique globale de l'échangeur
This work consists of developing a software tool based on the linear thermomechanical modeling of the heat exchanger using homogenization techniques. A methodology for modeling the heat exchanger constituted by stacking of different brazed fins and sheets is adopted. This methodology assumes that the global behavior of every layer of fins and sheets is found between two behavior limits determined by periodic mechanical approach (HMP) and periodic kinematical approach (HCP). These techniques are implemented for numerical application while studying global loading due to the temperature and pressure internal loads. A homogenization tool (HomPass) is then developed in order to calculate automatically equivalent behaviors to each layer of brazed fins and sheets. That contributes to the development of the final software tool (SiTEME) dedicated to the global thermomechanical study of the heat exchanger

L’objectiu general d’aquesta recerca és l’estudi de la funció de la taula periòdica en l’ensenyament de la química. L’estudi pretén identificar fins a quin punt l’ensenyament de la taula periòdica contribueix a perpetuar la idea què els àtoms són l’objectiu d’estudi de la química i no una eina per pensar en els canvis químics i incidir-hi de manera racional i raonable. La recerca es porta a terme sobretot en el marc de l’ensenyament preuniversitari, en el context de l’activitat científica escolar, més concretament de la química escolar, que és el marc teòric-didàctic en el qual es formulen les preguntes de la recerca. Per arribar a l’objectiu s’han definit tres focus d’anàlisi, i en relació a cadascun s’ha formulat una pregunta d’investigació i diversos objectius per respondre-la. Els tres focus d’anàlisi són: a) els articles sobre la taula periòdica publicats durant els últims 15 anys en una mostra de revistes d’impacte de didàctica de les ciències i de didàctica de la química, b) una mostra de llibres de text de química d’ESO i batxillerat, i c) les respostes d’una enquesta lliurada a un grup de professors d’aquests mateixos nivells escolars. Pel que fa a la mostra d’articles, es pregunta quins són els nuclis conceptuals amb més presència i quina és la funció docent que donen a la taula periòdica. Respecte a la mostra de llibres de text es pregunta en quin grau els nuclis conceptuals identificats en els articles estan presents en el relat d’aquests llibres i quina funció atorga aquest relat a la taula periòdica. Finalment, quant a les respostes del professors, es demana en quin grau les seves respostes inclouen els nuclis conceptuals identificats en els articles i quina funció es dóna a la taula periòdica, tenint en compte la seqüenciació de temes que els professors proposen per introduir aquesta taula a l’aula. Per respondre la primera pregunta, dirigida a la mostra acotada de revistes, es procedeix a la ressenya, classificació i anàlisi dels articles seleccionats mitjançant categories emergents. Els nuclis conceptuals que emergeixen són: a) el concepte d’element químic, b) el format de la taula periòdica com a problema, c) l’explicació de la periodicitat, d) el desenvolupament històric del sistema periòdic i e) les característiques generals de diversos elements químics. Mitjançant l’anàlisi de contingut dels articles a partir d’aquests nuclis conceptuals identifiquem les funcions següents: la funció de modelització, la funció classificadora, la funció heurística simbòlica i la funció heurística electrostàtica. Per respondre la segona pregunta, sobre els llibres de text, s’ha dissenyat una plantilla d’anàlisi i un instrument d’interpretació bidimensional (epistemològic-ontològic) basats en els nuclis conceptuals presents als articles. El resultat mostra que el concepte d’element químic apareix centrat en el caràcter atòmic; que el tema del format com a problema és inexistent; que la periodicitat hi apareix d’una forma més descriptiva que explicativa; i que el desenvolupament històric es presenta mitjançant una retòrica de lògica positivista i un “relat” comú que presenta variacions en funció de la visió dels elements. A partir de l’anàlisi i la interpretació d’aquests nuclis conceptuals, identifiquem les següents funcions en els llibres text: la funció classificadora i la funció heurística macro-micro. Per respondre la tercera pregunta s’ha dissenyat, a partir dels nuclis conceptuals presents als articles, una enquesta dirigida a un grup de professors i un instrument per interpretar-ne les respostes. El concepte d’element químic hi apareix de forma difusa; es té en compte la diversitat de formats, però no com a problema; i el desenvolupament històric es centra en la capacitat predictiva, ordenadora i explicativa com a característiques importants per l’acceptació de la taula periòdica per part de la comunitat científica. A partir de l’anàlisi i la interpretació dels nuclis conceptuals identifiquem les següents funcions: la funció classificadora i la funció explicativa. Dels resultats de l’anàlisi es desprèn que la funció classificadora, juntament amb els “relats” més habituals en l’ensenyament de la taula periòdica, contribueixen a perpetuar la idea de l’àtom com objecte d’estudi de la química. Es tendeix a descartar l’ús del mol i de l’àtom químic en el nivell “meso” com a eines de pensament, que poden ser útils als alumnes per explicar i intervenir en els canvis químics. Aquests canvis són, finalment, el principal objecte d’estudi de la química.
Esta investigación tiene el propósito general de estudiar la función de la tabla periódica en la enseñanza de la química. Pretende identificar hasta qué punto la enseñanza de la tabla periódica contribuye a perpetuar la idea de que los átomos son el objetivo de estudio de la química, más que una herramienta para pensar los cambios químicos e intervenirlos de manera racional y razonable. La investigación se centra especialmente en la educación escolar preuniversitaria, en el contexto de la actividad científica escolar, concretada en la química escolar, que es el marco teórico didáctico dentro del cual se abordan las preguntas de investigación. Para alcanzar este propósito, se han definido tres focos de análisis y en relación con cada uno se ha formulado una pregunta de investigación y diversos objetivos para responderla. Los tres focos de análisis son: a) los artículos sobre la tabla periódica publicados durante los últimos 15 años en una muestra de revistas de impacto de didáctica de las ciencias y de didáctica de la química, b) una muestra de libros de texto de química de ESO y bachillerato, y c) las respuestas a una encuesta suministrada a un grupo de profesores de los mismos niveles escolares. Respecto a la muestra de artículos, se pregunta cuáles son los núcleos conceptuales con mayor presencia y cuál es la función docente que otorgan a la tabla periódica. Respecto a la muestra de libros de texto, se pregunta en qué grado los núcleos conceptuales identificados en los artículos están presentes en el “relato” de estos libros y qué función otorga este relato a la tabla periódica. Finalmente, en relación a las respuestas de los profesores, se pregunta en qué grado sus respuestas incluyen los núcleos conceptuales identificados en los artículos y qué función se otorga a la tabla periódica, teniendo en cuenta la secuenciación de temas que los profesores proponen para introducirla en el aula. Para responder la primera pregunta, dirigida a la muestra de revistas acotada, se procede a la reseña, clasificación y análisis de los artículos seleccionados mediante categorías emergentes. Los núcleos conceptuales que emergen son: a) el concepto de elemento químico, b) la cuestión del formato de la tabla periódica como problema, c) la explicación de la periodicidad, d) el desarrollo histórico del sistema periódico y e) las características generales de diversos elementos químicos. Mediante el análisis de contenido de los artículos a partir de estos núcleos conceptuales identificamos las siguiente funciones: la función de modelización, la función clasificadora, la función heurística simbólica y la función heurística electrostática. Para responder la segunda pregunta, dirigida a los libros de texto, se ha diseñado una plantilla de análisis y un instrumento de interpretación bidimensional (epistemológico-ontológico) basados en los núcleos conceptuales presentes en los artículos. El resultado muestra que el concepto de elemento químico aparece centrado en el carácter atómico; la cuestión del formato como problema es inexistente; la periodicidad aparece de una manera más descriptiva que explicativa; y el desarrollo histórico se presenta mediante una retórica de lógica positivista y un “relato” común que presenta variaciones en función de la visión de elemento. A partir del análisis e interpretación de estos núcleos conceptuales identificamos las siguientes funciones en los libros de texto: la función clasificadora y la función heurística macro-micro. Para responder la tercera pregunta se ha diseñado, a partir de los núcleos conceptuales presentes en los artículos, una encuesta dirigida a un grupo de profesores y un instrumento para interpretar las respuestas. El concepto de elemento químico aparece difuso; se tiene en cuenta la diversidad de formatos aunque no como un problema; y el desarrollo histórico se centra en la capacidad predictiva, ordenadora y explicativa como características importantes para la aceptación de la tabla periódica por parte de la comunidad científica. A partir del análisis e interpretación de los núcleos conceptuales identificamos las siguientes funciones: la función clasificadora y la función explicativa. De los resultados del análisis se desprende que la función clasificadora, junto con los “relatos” más habituales en la enseñanza de la tabla periódica, contribuyen a perpetuar la idea del átomo como objeto de estudio de la química. Se tiende a descartar el uso del mol y del átomo químico en el nivel ‘meso’ como herramientas de pensamiento, que pueden ser útiles a los alumnos para explicar e intervenir en los cambios químicos. Estos cambios son, finalmente, el principal objeto de estudio de la química.
The main purpose of this research is to study the function of the periodic table in chemistry teaching. It aims to identify to what extent the teaching of the periodic table helps perpetuating the idea that atoms are the goal of studying chemistry, rather than a tool for thinking about chemical changes and acting on them both rationally and reasonably. The research specially focuses on high school scientific activity and in particular in school chemistry, which is the educational theoretical framework from which the research questions are addressed. To achieve this goal, three focal points of analysis are defined as well as one research question for each, and different objectives that allow answering them. The three focal points are: a) the articles on the periodic table published during the last 15 years in a sample of impact journals of science education and chemistry teaching, b) a sample of high school chemistry textbooks, and c) responses to an inquiry answered by a group of high school teachers. For the sample of articles the research question refers to the identification of the most frequent core concepts that appear in the articles and the teaching function that is given to the periodic table. For the sample of textbooks the research question refers to what extent the core concepts identified in the articles are present in the narrative of these books, and the teaching function given to the periodic table in them. Finally, regarding the teachers' responses, the research question refers to what extent their answers include the core concepts identified in the articles and the teaching function given to the periodic table by them, considering the sequencing of topics that teachers propose to introduce it in their classes. To answer the first question, regarding the sample of journals, a review, classification and analysis of selected articles is done by emerging categories. The most frequent core concepts are: a) the concept of chemical element, b) the issue of the format of the periodic table, c) the explanation of the periodicity, d) the historical development of the periodic system, and e) the general characteristics of different chemical elements. The functions of the periodic table are identified through the content analysis of the articles and it is based on the core concepts. The identified functions of the periodic table in the articles are: the modelling function, the classifying function, the symbolic heuristic function and the electrostatic heuristic function. To answer the second question, regarding the sample of textbooks, a template and a bi-dimensional interpreting tool (epistemological-ontological) based on the core concepts are designed. The main results show that the concept of chemical element focuses on the atomic nature; the issue of the format is non-existent; the periodicity appears in a more descriptive than explanatory way; and the historical development is presented by a logical-positivist rhetoric and a common narrative that has variations depending on the view of the element. Based on the analysis and interpretation of the core concepts the following functions of the periodic table are identified in the textbooks: the classifying function and the macro-micro heuristic function. To answer the third question, it has been designed a directed inquiry for a group of teachers and a tool to interpret their responses, both based on the core concepts identified in the articles. The concept of chemical element appears to be diffuse, the issue of the format is considered important for the teachers but not problematic; and the historical development focuses on the predictive, explanatory and ordering power of the periodic table as important features for its acceptance by the scientific community. Based on the analysis and interpretation of the core concepts the following functions of the periodic table are identified in the teachers' responses: the classifying function and the explanatory function. The most highlighted outcomes show that the classifying function along with the most usual narratives in the teaching of the periodic table help perpetuating the idea of the atom as a chemistry object of study. It is not mostly considered the use of the mole and the chemical atom in the 'meso' level as thinking tools that could be helpful for students in explaining and intervening on chemical changes. These changes are finally the main chemistry object of study.

Ce travail tente de développer des outils numériques efficaces pour une approche plus rationnelle et moins empirique du dimensionnement à la ruine des ouvrages de génie civil. Contrairement aux approches traditionnelles reposant sur une combinaison de calculs élastiques, l'adoption de coefficients de sécurité et une vérification locale des sections critiques, la théorie du calcul à la rupture nous semble être un outil prometteur pour une évaluation plus rigoureuse de la sécurité des ouvrages. Dans cette thèse, nous proposons de mettre en œuvre numériquement les approches statique par l'intérieur et cinématique par l'extérieur du calcul à la rupture à l'aide d'éléments finis dédiés pour des structures de plaque en flexion et de coque en interaction membrane-flexion. Le problème d'optimisation correspondant est ensuite résolu à l'aide du développement, relativement récents, de solveurs de programmation conique particulièrement efficaces. Les outils développés sont également étendus au contexte de l'homogénéisation périodique en calcul à la rupture, qui constitue un moyen performant de traiter le cas des structures présentant une forte hétérogénéité de matériaux. Des procédures numériques sont spécifiquement développées afin de déterminer puis d'utiliser dans un calcul de structure des critères de résistance homogènes équivalents. Enfin, les potentialités de l'approche par le calcul à la rupture sont illustrées sur deux exemples complexes d'ingénierie : l'étude de la stabilité au feu de panneaux en béton armé de grande hauteur ainsi que le calcul de la marquise de la gare d'Austerlitz
This work aims at developping efficient numerical tools for a more rational and less empirical assessment of civil engineering structures yield design. As opposed to traditionnal methodologies relying on combinations of elastic computations, safety coefficients and local checking of critical members, the yield design theory seems to be a very promising tool for a more rigourous evaluation of structural safety. Lower bound static and upper bound kinematic approaches of the yield design theory are performed numerically using dedicated finite elements for plates in bending and shells in membrane-bending interaction. Corresponding optimization problems are then solved using very efficient conic programming solvers. The proposed tools are also extended to the framework of periodic homogenization in yield design, which enables to tackle the case of strong material heterogeneities. Numerical procedures are specifically tailored to compute equivalent homogeneous strength criteria and to use them, in a second step, in a computation at the structural level. Finally, the potentialities of the yield design approach are illustrated on two complex engineering problems : the stability assessment of high-rise reinforced concrete panels in fire conditions and the computation of the Paris-Austerlitz railway station canopy

Les transducteurs ultrasonores capacitifs micro-usinés (cMUT : capacitive Micromachined Ultrasound Transducers) apparaissent, au vu de leur maturité croissante, comme une alternative de plus en plus viable à la technologie piézoélectrique. Caractérisés par une large bande passante et une large directivité, ces transducteurs sont des solutions intéressantes pour le développement de sondes ultrasonores « exotiques » dont les spécifications sont difficilement atteignables en technologie piézoélectrique. C'est dans ce contexte et fort de l'expérience acquise par notre laboratoire sur cette technologie pendant plus d'une dizaine d'années, que s'est inscrit ce travail de thèse. L'originalité du travail rapporté ici est d'aller de l'analyse du comportement général des barrettes cMUT jusqu'à un exemple précis de conception de sonde cMUT pour l'évaluation du tissu osseux. Des outils de modélisation précis et rapides, basés sur l'introduction de conditions de périodicité, ont été développés. Plusieurs modèles ont ainsi été mis en place afin d'adapter la stratégie de modélisation à la topologie du dispositif cMUT à modéliser : cellule isolée, colonne de cellules, matrice de cellules et élément de barrette. Ces modèles ont permis d'étudier le comportement des éléments de barrette cMUT et d'améliorer notre connaissance sur les mécanismes physiques mis en jeu. De cette façon, l'origine des effets de baffle, problème récurrent du comportement des barrettes cMUT, a clairement été interprété par l'intermédiaire d'une analyse modale. Des solutions ont ainsi été identifiées et proposées afin d'optimiser le comportement des barrettes cMUT, de façon à réduire la présence des effets de baffle et à augmenter leur bande passante. Le développement d'une barrette cMUT dédiée à l'évaluation du tissu osseux est présenté dans sa totalité, afin d'illustrer les différents aspects liés à la conception d'une sonde de cette technologie. Un travail original de caractérisation a été réalisé sur cette barrette, afin d'estimer l'homogénéité inter-cellules à l'échelle de l'élément et l'homogénéité inter-éléments à l'échelle de la barrette. Enfin, une confrontation a été réalisée avec une sonde PZT de même topologie sur plusieurs fantômes osseux. Il a ainsi été démontré que la sonde cMUT permettait la détection d'un plus grand nombre de modes guidés, et par conséquent, une meilleure évaluation du tissu osseux
Following recent advances, the capacitive Micromachined Ultrasound Transducers (cMUT) technology seems to be a good alternative to the piezoelectric technology. For specific applications, the requirements and specifications of the probe are sometimes difficult to obtain with the traditional PZT technology. The cMUT technology, with both large bandwidth and angular directivity, can be an interesting way to overcome these limitations. This PhD has been carried out in this context, in a laboratory which has nearly 10 years of experience in the field of cMUT technology. The originality of the work sustained in this PhD is that it covers the cMUT technology, from general aspects dealing of modeling and characterization up to a complete example of cMUT-based probe applied to the assessment of cortical bone. Fast and accurate modeling tools, based on periodicity conditions, have been developed. Several models have been proposed to match the modeling strategy to the topology of the cMUT array : isolated cell, columns of cells, 2-D matrix of cells and array element. These models have been used to analyze the cMUT array behavior and to understand how mutual couplings between cMUTs impact the response of one element. Origins of the baffle effect, well-known as a recurrent problem in cMUT probe, have been explained using an original method based on the normal mode decomposition of the radiated pressure field. Thus, solutions have been identified and tested to optimize the cMUT frequency response, i.e. to increase the bandwidth, and to suppress parasitic disturbances linked to baffle effect in the electroacoustic response. The development of a dedicated cMUT array for the assessment of bone tissue is accurately detailed in the manuscript, including description of the design rules, fabrication steps and packaging procedure. An original characterization work has been carried out in order to check the device homogeneity, first from cell to cell and then from element to element. Finally, a comparison with a PZT probe with the same topology has been performed on bone mimicking phantom. Nice results has been obtained, showing that cMUT probe allows detecting higher number of guided modes in the cortical shell, and consequently, improving the cortical bone assessment

This thesis is focused on usage of computer game (adventure game) in teaching of chemistry. Game is situated to the town of Český Krumlov and contains set of tests from nomenclature (names and symbols of chemical elements). This game can be used to motivate students to study chemistry on lower grades of grammar schools and higher grades of elementary schools.

1 Abstract The subject of this thesis was creating of teaching material for an interactive whiteboard using the SMART Notebook program. The material was created in form of interactive presentations designed to be used in chemistry lessons at secondary schools. The unifying theme of presentations was the 14th group of the periodic table of elements. The thesis also includes a description of the way the presentations were made and instructions for teachers how to work with them. It also introduces some advantages and disadvantages of working with the SMART Notebook software. Key words: Interactive whiteboard, SMART Notebook, group 14 of the periodic table of elements, presentations, carbon, silicon, tin, lead, germanium

The subject of this thesis was creating of teaching material for an interactive whiteboard using ActivInspire program. The material was created in a form of interactive presentations designed to be used in chemistry lessons at secondary schools. The theme of these presentations was the 15th group of the periodic table of elements. The thesis also includes a description of the way the presentations were made and instructions for teachers how to work with them.

Thesis (Ph. D.)--University of Georgia, 2002.
Directed by Henry F. Schaefer, III. Includes articles published in Pure and applied chemistry, and Journal of chemical physics, and an article submitted to Chemical physics letters. Includes bibliographical references (leaves 81-98).

碩士
國立臺灣大學
土木工程學研究所
107
The isolation system has flourished to equip with the structure in recent years. The traditional isolation system has been proven to enhance the horizontal seismic performance of many isolated structural system, but without the capability of isolating vertical earthquakes. Seismic metamaterials were known as conceptual materials in research and development field in recent years. Within the dispersion characteristics, seismic wave can be attenuated or controlled within acceptable range. This study aims to evaluate and analyze the shaking table test results of one-dimensional periodic structures. In this thesis, the results of the shaking table test have been analyzed. The influences of the experimental equipments of the tests have been discussed. Calculation using formulas and numerical model analysis via SAP2000 software were carried out. The horizontal test results of the concrete foundation were found to be affected by the stiffness of the bolts. Also, the influences of the different natural frequency of the periodic foundation and concrete foundation on the test results have been analyzed. The response spectrum analysis has been carried out for the shaking table test results, and the spectral acceleration response of the one-dimensional periodic foundation is smaller than the concrete foundation. In this study, ABAQUS numerical model of one-dimensional periodic structure has been established. The influences of the stiffness of the bolt were simulated by the contact stiffness. Since the stiffness of rubber under tension and compression were different, the vertical stiffness of the rubber was enhanced by calculating the compression modulus. Therefore, the numerical model can successfully simulate the experimental results. By utilizing the influences of the material properties on the periodic foundation band gap, a parametric analysis model was designed by reducing the Young’s modulus of the rubber and increasing the thickness of the foundation. The horizontal frequency band gap of the parametric model is 1.5Hz to 50Hz, the vertical frequency band gap is 5.3Hz to 50Hz. The results of parametric study with periodic foundation models show that both horizontal and vertical response are reduced within the frequency band gap. Beyond the frequency band gap, the horizontal responses were affected by the input earthquake frequency, responses reduced at the natural frequency of the model when subjected to high frequency earthquake but amplified when struck by low frequency earthquake. The vertical responses were not affected by the input earthquake frequency, responses always amplified at the natural frequency of the model.

碩士
國立臺灣師範大學
化學研究所
88
The main purpose of this study aims at evaluating the effectiveness of the web-based chemistry teaching materials in the chapter of “The Atom Structure and the Periodic Table”. Some differences between web-based material and traditional textbook are discussed in this research. The development the hypertext courseware was based on the scheme of the instructional hypertext and the suggestions on the “The Atom Structure and the Periodic Table”. Empirical research was carried out in order to evaluate its effectiveness. 175 private senior high school students were selected by purposeful sampling, and joined the pre-test, self-study on the chapter and post-test. In addition, the students who studied the hypertext courseware were questionnaire their opinions about the software. The result of the pre-test showed that the controlled group and the experimental group didn’t have significantly outperformances with each other. Otherwise, the students'' prior knowledge level was classified according to the pre-test. The result of the post-test indicated that the students who study the hypertext courseware didn’t outperformed those who study the lecture text significantly. Only the students of high prior knowledge made significantly outperformance in the hypertext courseware than in the lecture text. The empirical research result suggested that students with higher prior knowledge get high benefits in the hypertext courseware. The large amount of pictures in hypertext courseware could raise the interesting in learning this chapter. However, some misconceptions such as “ H atom structure” and “Ionization energy” still rooted in students. In addition, the questionnaires revealed that the students who study the hypertext courseware responded positively to the program and considered it a great deal aid in learning this lesson. However, they suggested more efforts should be made to increase the interaction and in the perfection of the appearance design.

碩士
國立臺北教育大學
數位科技設計學系(含玩具與遊戲設計碩士班)
104
Periodic Table is the basis for junior high school students to learn science.All the science applications are extended by the beginning of a periodic table.Therefore, students need to have a complete understanding on periodic table that can learn science better.Traditionally,a periodic table teaching is to give students Chinese words, students write in English, or English to students, students write words in Chinese.However, in the information era, appear of digital game whether allows teachers to teach the periodic table can have different teachings.Not only allows students to learn the periodic table better, but also allows students to feel interesting, is the main point of this research. This research is to construct a "Periodic table Teaching Platform", the first step is to teach periodic table, with "periodic table image memory method" as the theoretical basis.After that ,design 9 kinds of cross-platform HTML5 games by construct2 , Elementary level Games includes "Periodic table choice question","Periodic table challenge","Periodic table Sushi train ".Intermediate level game includes "Periodic table Bingo", "Periodic table Fruit Slicer", " Periodic table Card Match".High level game incluses "Periodic table Air Combat Game ", "Periodic table Mario", "Look for Periodic table".Not only can improve students' proficient ability of the periodic table,bue also in final level game can challenge "Boss".In all games you can upload scores to rank.Scores in games can be converted into experience points, money. Experience points can upload level, and money can buy equipment.Finally you can challenge Boss to complete the final stages of learning.This teaching platform can be used for window, Android, IOS.All cross-platform system, whether using a computer, smart phone, tablet computer, students can use this teaching platform everywhere,at any time.And you don’t necessarily need to use the keyboard when using your computer.You can use USB gamepad to play "Periodic table Mario". In order to evaluate the effectiveness of learning teaching platform, this semester I fill the position of seventh grade "Multimedia Periodic table" club teacher.The club have 12 members.Evenyone can play each game,and analyze student’s progress situation,and finally give students questionnaires to fill out. In this research, finally take students’ wrong topic to do statistics and questionnaire statistics.The final target hopes to reach "game-based leaming".This research can be extended that all teachers’ teaching content can be made into the game for students to play.Not only can achieve the purpose of teaching and entertaining,but also teachers can analyze student’ learning. The conclusions of this research: 1. "Periodic table Fruit Slicer" is the highest rating in all games,not only interesting but also can help recite periodic table. 2. When students play 「Educational games」,it must beforehand understand the subjects can reached the standard rapidly . 3. When playing cooperative games, the strongest combination is not always most rapidly reached the standard ,because teamwork is very important.

Yes
In this study we examine the structures of ten personality inventories widely used for personnel assessment, by mapping the scales of personality inventories (PIs) to the lexical Big Five circumplex model resulting in a ‘Periodic Table of Personality’. Correlations between 273 scales from ten internationally popular PIs with independent markers of the lexical Big Five are reported, based on data from samples in two countries (UK N = 286; USA N = 1,046), permitting us to map these scales onto the AB5C framework. Emerging from our findings we propose a common facet framework derived from the scales of the PIs in our study. These results provide important insights into the literature on criterion-related validity of personality traits, and enable researchers and practitioners to understand how different PI scales converge and diverge and how compound PI scales may be constructed or replicated. Implications for research and practice are considered.

Scerriâ s book demonstrates how one of the most important classification systems has evolved and what kinds of conceptualizations and classification criteria are at work in it. It is probably the best book about the best classification system ever constructed. The book review considers the theoretical basis of this classification system as well as implications for the field of Knowledge Organization.

In Chapter 1, I discuss the synthesis and characterization of lithium tris(pyrazolyl)hydroborato complexes, [TpR1,R2]Li. Group 1 [TpR1,R2]M complexes serve as key starting points to access many other main group and transition metal complexes; however, the synthesis and crystal structures of [Tp R1,R2]Li has not been reported. Molecular structures of [TpBut]Li and [TpBut,Me]Li show these complexes are trigonal pyramidal, an unusual geometry for lithium. These complexes are also able to bind small molecules to form four-coordinate pseudo-tetrahedral complexes, [Tp]Li-L (L = MeCN, pzButH, and H2O). The binding constants for the association of acetonitrile to [TpBut]Li and [TpBut,Me]Li are 0.84M-1 and 0.96M-1, respectively, indicating that the dissociation of MeCN is facile in solution. In addition, [TpBut,Me]Li serves as transmetallating agent to yield the cadmium halide complexes, [TpBut,Me]CdX (X = Cl, Br, I). In Chapter 2, I discuss the synthesis and characterization of organometallic cadmium complexes supported by the nitrogen-rich multidentate ligands, tris(pyridylthio)methane, [Tptm]H; tris(1-methyl-imidazolylthio)methane, [TitmMe]H; and tris(1-methyl-benzimidazolylthio)methane, [TitmiPrBenz]H. These ligands are in the nascent stages of development and there are only a few metal [Tptm] and [TitmMe] complexes in the literature. An investigation of the reactivity of [L]CdN(SiMe3)2, [L]CdOSiMe3, and [L]CdOSiPh3 ([L] = [Tptm], [TitmMe], [TitmiPrBenz]) shows these complexes provide access to a variety of organometallic cadmium complexes, [L]CdX, (X = OAc, Cl, Br, O2CH, NCO). The characterization of cadmium acetate and formate complexes is significant due to their structural similarity with the metal bicarbonate intermediate formed by zinc and cadmium-substituted carbonic anhydrase. In addition, the synthesis and characterization of cadmium methyl complexes, [L]CdMe, is discussed. The application of heat to a mixture of [TitmiPrBenz]H and CdMe2 results in isomerization of the ligand to [S3-TitmiPrBenz]CdMe. This sulfur-rich [S3-TitmiPrBenz] ligand is not reported in the literature and is ripe for further investigation. The solid state structures of these compounds provide a comparison with biologically relevant [Tp] or [Tm] cadmium methyl complexes in the literature. In Chapter 3, I describe the synthesis and structural characterization of [BmButBenz]M (M = Na, K) and [BmRBenz]Ca(THF)2 (R = Me, But) are discussed. The sulfur-rich tripodal ligand tris(imidazolylthio)hydroborato, [Tm], was previously designed to serve as a softer version of the [Tp] ligand. Metal [Tm] complexes are prevalent in the literature and have often been used as molecular mimics of sulfur-rich enzyme active sites. Recently, the benzannulated [TmRBenz]M complexes were reported and were found to promote k3 coordination toward the metal center. To allow for an in-depth investigation of the newly synthesized [BmRBenz] class of ligand, the [BmButBenz]M (M = Na, K, Ca) complexes were synthesized and compared to previously reported metal [BmMeBenz]M complexes. Additionally, the [BmMeBenz]2Ca(THF)2 was synthesized and characterized via X-ray diffraction. The molecular structure of [BmMeBenz]2Ca(THF)2 shows the complex is monometallic with an uncommon eight-coordinate dodecahedral calcium center. [BmMeBenz]2Ca(THF)2 is the first molecular structure of calcium coordinated to the [Tm] or [Bm] ligand class. In Chapter 4, I discuss the synthesis and characterization of mercury alkyl complexes supported by the [TmMe], [BmR], [TmRBenz] and [BmRBenz] ligands (R = Me or But). As previously mentioned, [Tm]M complexes are considered biologically relevant molecular models of enzyme active sites. With this in mind, [TmBut]HgR (R = Me,Et) complexes have served as mimics for the mercury detoxification enzyme MerB. A previous study by our group showed that the adoption of multiple coordination modes of the ligand in [TmBut]HgR plays a significant role in the activation of the Hg-C bond toward protonolysis. The molecular structures of the [TmR], [BmR], [TmRBenz], and [BmRBenz] mercury alkyl complexes show that they adopt various coordination modes, ranging from k1 to k3. Preliminary competition experiments in which benzenethiol was added to [TmR]HgEt and [TmRBenz]HgEt indicate that the Hg-C bond in [TmMeBenz]HgEt was cleaved faster than that in [TmMe]HgEt. Conversely, the Hg-C bond in [TmBut]HgEt was cleaved faster than that in [TmButBenz]HgEt, indicating that benzannulation and the size of the R-group on the [Tm] ligand play important roles in Hg-C bond cleavage.

碩士
國立臺北科技大學
互動媒體設計研究所
105
The periodic table of elements is a collection of the elements discovered on earth. However, this topic also makes up an important chapter in the curriculum guidelines of our country. In a traditional class, a teacher usually asks the students to memorize it at an early stage of learning. The students are required to memorize each element and face the pressure of testing without understanding the reasons behind the arrangements. This lack of learning motivation subsequently causes learning inefficiency. To prevent students from giving up on the contents in later courses due to their lack of learning motivation at an early leaning stage, this study adopts Blooms Taxonomy as the pilot study and designs Digital Game-Based Learning content that combines virtual reality and the periodic table of elements by referring to the ARCS model of motivation design to make the abstract knowledge in the textbook more tangible. Starting from the two major design perspectives of “learning” and “challenge,” the study further selects the highly interactive and coordinate-tracking HTC Vive as the medium and then evaluates whether the creation helps increase students’ interest in learning the periodic table of elements, as well as whether their subsequent learning purposes in chemistry classes are improved using the Instructional Materials Motivation Survey (IMMS). This creative study includes 59 questionnaires, and most of the research results indicate maximum performance in the ARCS model. In addition to increasing students’ learning motivation, this creative study can also provide a modifying direction for future works based on suggestions given by the junior high school teachers and students in the interview feedback.

No
New representations and efficient calculation methods are derived for the problem of propagation from an infinite regularly spaced array of coherent line sources above a homogeneous impedance plane, and for the Green's function for sound propagation in the canyon formed by two infinitely high, parallel rigid or sound soft walls and an impedance ground surface. The infinite sum of source contributions is replaced by a finite sum and the remainder is expressed as a Laplace-type integral. A pole subtraction technique is used to remove poles in the integrand which lie near the path of integration, obtaining a smooth integrand, more suitable for numerical integration, and a specific numerical integration method is proposed. Numerical experiments show highly accurate results across the frequency spectrum for a range of ground surface types. It is expected that the methods proposed will prove useful in boundary element modeling of noise propagation in canyon streets and in ducts, and for problems of scattering by periodic surfaces.

碩士
朝陽科技大學
應用化學系碩士班
101
ABSTRACT The study aimed at investigating the feasibility of integrating the chemistry periodic table into science curriculum of the fifth and sixth grades in elementary schools. Based on the teaching effectiveness, an assessment of the feasibility was carried out. 178 fifth and sixth graders at an elementary school in Taichung were chosen as the object of the study for one and a half year. The questionnaire with a total of 214 copies was conducted. After the statistical analysis, the findings were summarized as follows. After being taught with the chemical elements, the students’ overall learning attitudes were revealed as follows. I. The students reacted positively as learning the chemical elements and the chemistry periodic table. Among the cognitive factors, affective factors and the scientific attitude factors, the scientific attitudes presented the best. There is a significant and highly positive correlation between the three factors and the scientific attitudes presented the best among the three factors. II. The fifith and sixth graders’ ability for learning the chemistry periodic table is able to be expected. III. And the overall opinion revealed from the questionnaire was that the adoption of teaching the fifth and sixth graders chemical elements was agreed. On the whole, it is proposed that intergrating the chemistry periodic table into science curriculum of the fifthe and sixth grade is able to be promoted.

碩士
國立高雄師範大學
科學教育研究所
95
The purpose of this study was to understand the cramming school`s famous chmical teacher`s teaching. To know what representations the teacher use and how to use those representations make important knowledge link to each other,and help students efficient in study. And to understand the teacher`s value and theory behind those representations. In Taiwan, attend cram school was very popular, and everybody want to know the study about cram school , so researcher used qualitative methods for data collection in the study .They were systematic classroom observation, teacher-student interview, and questionnaire investigation. Following are the results from the study: 1. The teacher usually guided question , review appeal students`attention. Coming content ,representations are full. 2. The teacher`s teaching structure is first: clear the main study object in the curriculum , secend is to find the trait and the point in the curriculum , third is to say concept and use practical things to explain not easy understand contents. The teacher use better ways to explain harder question ,and always talk to students. Fourth is help students know what lows of vhose contents and do analyze. 3. The value of the teacher is help students were understand content .Not only remember those content, but help students study deeply, and help students got points .

碩士
國立高雄師範大學
文化創意設計碩士學位學程
107
ABSTRACT Table games are popular in all ages in recent years, and they are rich in game learning activities. As the name implies, they are games played on a table or any other plane. This study uses the Evaluation Grid Method (EGM). For 8 pre-school special education field workers with high involvement, the use of board games for teaching and in-depth interviews. Combined with the "Kano Model", the Kano Model is used to classify the attributes of the fascinating elements used in preschool special education courses to attract users. In combination with the abstract charm of the quality characteristics extracted by in-depth interviews, the table games are designed for the pre-school special education courses and do not have two-way questionnaires. The questionnaires are conducted using the instant and simple cloud questionnaire survey, and the testees can always and anywhere. Use the mobile device to fill out the questionnaire, shorten the time of collecting the questionnaire data and ensure the correctness of the original data. The questionnaire statistics use the two-dimensional quality model to analyze the user's satisfaction with the fascinating attributes of the table games, and classify the important factors of the attribute charm quality, in order to provide the board game designers and developers to develop innovative table games merchandise charm factors, will be demanded It is realized in the design and development of commodities to enhance the wider and more accurate acquisition of board games products by future users, so as to be effectively applied to more learning objects and learning purposes.

Atualmente, vários investigadores sobre o ensino das ciências defendem a valorização deste ensino através do recurso à História da Ciência e à sua Epistemologia, valorização essa que passa pelo desenvolvimento do espírito científico, das competências e das atitudes construtivas dos alunos que esse recurso poderá proporcionar e que são indispensáveis na educação de jovens que se deseja estejam aptos a desempenhar um papel importante no progresso da sociedade. A presente investigação desenrolou-se no sentido de dar resposta à seguinte questão: “Em que medida o recurso à História da Ciência pode melhorar o processo ensino/aprendizagem da Química e a imagem que os alunos têm desta Ciência?” Na concretização de tal objetivo pesquisou-se o efeito da utilização em sala de aula, num ambiente construtivista de aprendizagem, de uma estratégia de ensino/aprendizagem de uma área da Química (Tabela Periódica), recorrendo a materiais curriculares que permitiram a introdução de aspetos históricos. O “Vê” heurístico ou “Vê” epistemológico – um instrumento coerente com a visão construtivista da natureza do conhecimento – esteve na base da conceção do presente estudo. Descreveu-se, sumariamente, alguns contributos da Epistemologia e da Psicologia Educacional para o campo da educação em ciência. Na recolha de dados optou-se por um método predominantemente qualitativo e de orientação interpretativa. Como instrumentos de pesquisa, concebidos de forma a permitirem obter respostas o mais representativas possível de molde a cumprir o objetivo do estudo, foi aplicado um questionário em dois momentos diferentes (antes e depois do estudo), realizada uma visita de estudo, feitos registos de observação, fichas de trabalho e um teste final. A apreciação das respostas ao questionário permitiu concluir que uma percentagem significativa de alunos tinha modificado a visão dogmática que possuíam acerca da Ciência. Os resultados do teste final evidenciaram uma boa aprendizagem por parte dos alunos daquele tema. A transformação de registos e a análise dos resultados permitiu formular alguns juízos cognitivos dos quais os mais preponderantes são: a) a História da Ciência é um importante recurso didático que permite aos alunos entender como se constrói o conhecimento científico, evitando que tenham da Ciência uma visão dogmática; b) a História da Ciência proporciona um melhor encadeamento entre os conhecimentos e ajuda os alunos a entender o significado dos conceitos, uma vez que tomam consciência das dificuldades encontradas na sua construção; c) para que os estudantes construam, de forma significativa, modelos conceptuais cientificamente corretos contribuem actividades que ofereçam ao aluno a oportunidade de explorar, criticar e refletir sobre o seu próprio funcionamento cognitivo e sobre os processos que utiliza para aprender e ajuizá-los criticamente. Pode-se sintetizar os juízos cognitivos formulados, afirmando que o recurso à História da Ciência contribuiu para uma mudança na imagem que os alunos tinham da Ciência e que uma estratégia baseada na História da Ciência proporcionou uma boa aprendizagem. Foram também enunciados alguns juízos de valor fundamentados na investigação.
Nowadays, several researchers in the field of science teaching have pushed towards valuing this branch of teaching through History of Science and its Epistemology. Such valuing is also connected to the development of a scientific spirit, of competences, and the constructive attitudes this resource might provide, which are core for the education of young people who, desirably, will be fit to take a major role in the progress of society. The following research was undertaken as a way to answer the question: “In what way might resorting to the History of Science improve the teaching/learning process and the view students have of this Science?” To reach this goal, a teaching/learning strategy in the field of Chemistry (the Periodic Table) was studied, using a constructivist learning environment in the classroom. This method made it possible to introduce historical features through the curricular materials in use. The heuristic or epistemological V – an instrument coherent with the constructive view of the nature of knowledge – was the basis of this study conception. A few contributions of Epistemology and Educational Psychology in the field of education in science were briefly described. In data collection, a predominantly qualitative and interpretative orientation method was taken. As research instruments, developed in a way which would allow for the most representative possible answers to be obtained in line with the project’s objective, a questionnaire was applied in two different moments (before and after the study), a field trip was taken, observation records registered, worksheets assigned and a final test submitted. The appreciation of the answers to the questionnaires led to conclude that a significant percentage of the students had changed their dogmatic view on Science. The results of the final test also display a good learning of the subject. The transformation of records and result analysis made it possible to formulate some cognitive judgements, from which the most important are: a) History of Science is an important didactic resource which allows students to understand how scientific knowledge is constructed, thus avoiding a dogmatic view of Science; b) the History of Science provides a better way of understanding how the building blocks of knowledge fit together and helps students understand the meaning of different concepts, since they become aware of the difficulties in their build-up; c) for students to be able to build scientifically accurate conceptual models in a significant manner, a great contribution can be made by the way of activities offering them a chance to explore, criticize and reflect on their own cognitive functioning and on the processes they use to learn. One can summarize the formulated cognitive judgements by stating that the resort to History of Science contributed to a change in how students regarded Science, and that a strategy based on the History of Science has led to a good learning process. Some value judgements fundamented by the research were also cited.

Vegetation establishment is one of the major rehabilitation methods that are used to stabilize, cover, to minimize, mitigate or remove the contaminants from tailings storage facilities (TSF’s). Phytostabilization is a useful mechanism by which plants limit the contamination of natural systems with toxic elements. For successful occurrence of phytostabilization on mine tailings, it is vital to establish plant species that can survive the hostile conditions of the substrate. Major problems encountered with vegetation covers is the lack of natural soil properties e.g. soil structure, organic carbon and also hostile chemical conditions. Only a few species are tolerant to the different negative properties of the tailings. The main aim of this project is to identify plant species that can be used for vegetative rehabilitation of nine different types of tailings material including gypsum, gold, platinum, kimberlite, coal, fluorspar and andalusite tailings. The ability of 28 different plant species to survive in the tailings was assessed by statistically calculating the growth potential of the species and summarizing the data in graphs and an index table that calculates a specific merit value for each of the tailings-species combinations. The various plant stress factors that the species exhibited were also documented. Finally, the results were correlated with a soil physical and -chemical baseline study of the tailings to provide insight into successes and failures of certain species. The final results identified various successful tailings-species combinations, as well as failures. The index table proved to be a useful tool to identify suitable species for establishment on various tailings. The baseline study of the different tailings could be used to explain why certain species could be established successfully, as well as the reason why some species did not survive.
M (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Orientação: Maria Nubélia Silvestre Bravo ; co-orientação: Manuel José Simões Loureiro
A avaliação contínua é um importante instrumento à disposição do professor. O presente trabalho estuda a medida em que um conjunto de conteúdos ministrados no 10º ano do ensino secundário, acompanhados de procedimentos baseados na avaliação contínua, pode contribuir para melhorar o desempenho e a aprendizagem relativamente a quatro elementos químicos da tabela periódica, nomeadamente o oxigénio, o hidrogénio, o carbono e o azoto. O trabalho será realizado em três turmas do ensino secundário. Os conteúdos programáticos relativos à “Tabela periódica-organização dos elementos químicos” a desenvolver nas três turmas serão os mesmos, mas ministrados por duas docentes distintas. Em duas das turmas, e durante quatro aulas, serão elaborados pequenos testes no início de cada aula sobre a matéria lecionada na aula anterior, que serão recolhidos e classificados pela docente por forma a averiguar uma esperada evolução. Nestas turmas as aprendizagens relativas a estes testes serão avaliadas de forma contínua. Na outra turma, turma de controlo, o programa será tratado da forma tradicional. No final proceder-se-á ao tratamento dos dados recolhidos e à elaboração das conclusões e de possíveis recomendações.
Continuous assessment is an important tool available to the teacher. This paper examines the extent to which a set of content taught in 10th grade high school, accompanied by procedures based on continuous assessment, can help improve the performance and learning for four chemical elements of the periodic table, including oxygen, hydrogen, carbon and nitrogen. Work will be performed in three middle school classes. The syllabus for the "Periodic table of the chemical elements-organization" to develop the three groups will be the same, but taught by two different teachers. In two of the classes, and for four lessons will be drawn up small tests at the beginning of each class on the subjects taught in the previous class, which will be collected and graded by the teacher in order to ascertain an expected evolution. In these classes the learning outcomes related to these tests will be evaluated continuously. In another class, classroom control, the program will be treated in the traditional way. In the end it will proceed to the processing of data collected and the preparation of findings and possible recommendations.