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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

O ensino por investigação abrindo espaços para a argumentação de alunos e professores do ensino médio

Bianchini, Thiago Bufeli [UNESP] 28 September 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-28Bitstream added on 2014-06-13T19:52:39Z : No. of bitstreams: 1 bianchini_tb_me_bauru.pdf: 683609 bytes, checksum: ef65f80c6217a55d4db4bb22436bf15c (MD5) / Nas últimas décadas, o Ensino de Ciências vem buscando estratégias que favoreçam o entendimento dos conteúdos científicos ou, como indica Driver (1999), a enculturação da Ciência (DRIVER, CAPECCHI E CARVALHO, MORTIMER, 2000), além da formação de alunos e professores críticos e reflexivos. O uso da argumentação em salas de aula pode se tornar grande aliada na formação de jovens pensadores e críticos, que consigam utilizar seus pensamentos em favor próprio e em conjunto, que sejam capazes de discutir problemas e propor soluções, não apenas na escola, mas em seu dia a dia. Para favorecer a argumentação, foi utilizado um minicurso investigativo com o tema Forças intermoleculares. Nossa proposta de trabalho procurou investigar quais são as potencialidades do uso integrado desses referenciais teóricos e qual a contribuição de uma proposta de minicurso invesetigativo no desenvolvimento de habilidades de argumentação em alunos e futuros professores além de analisar a proposta investigativa utilizada. Os dados analisados foram divididos em três categorias, i) a proposta do minicurso investigativo com base na classificação de atividades de ensino proposta por Canal (2000), ii) a qualidade da argumentação com Osborne et al (2004) e iii) a atuação do professor na elaboração dos argumentos dos alunos com Mendonça e Justil (2009). Os resultados mostram que a atividade proposta favoreceu a argumetnação dos alunos e professores, possibilitando a abertura de espaços na sala de aula para que ocorra diálogo entre os alunos e os professores. Pode-se perceber o papel fundamental do professor na elaboração dos argumentos dos alunos, pois, se os mesmos não direcionarem as discussões, os argumentos podem ser mal elaborados ou mal explorados / In recent decades, the Teaching if Science has been searching for strategies that enhance the understanding of scientific content or, as indicated by Driver (1999), enculturation of Science (DRIVER, Capecchi and CARVALHO, MORTIMER, 2000) and the training of teachers ans students to be critical and reflective. The use of argumentation in the classroom can become a great ally in forming young thinkers and critics, who can use their own behalf and thoughts together; they can discuss problems and propose solutions, not just in shool but in their day by day. To facilitate the argument we used an investigate shor course with the theme Intermolecular Forces. Our proposal of work aimed to investigate what are the potential use of integrated theoretical and the contribution of a proposed short course in the development of investigate reasoning abilities in students and future teachers as well as used to analyze the research proposal. Data were divided into three categories, i) the proposed investigative mini course based on the classification of educational activities proposed by Canal (2000), ii) the quality of argumentation with Osborne et al (2004) and iii) the performance of teacher in preparing students with the arguments of Mendonça and Justi (2009). The results show that the proposed activity favored the argument of the students and teachers, enabling the opening of spaces in the classroom dialogue to occur between students and teachers. It can be noticed the teqacher's role in the development of students arguments, because if they do not guiding discussions arguments can be poorly designed or poorly explored
12

Development of polarizable water models

Cao, Bei, 曹蓓 January 2015 (has links)
Polarization plays a significant role in the physical and chemical properties of water, thus polarizable water models have been extensively evolved and studied in the past several decades. In this dissertation, two polarizable water models have been extended, and some physical properties in gas phase and condensed phase were studied and analyzed. It was verified that the out-of-plane polarization effect is of great importance in some physical properties. Besides, we proved that there are some connections between these two models, although they were derived from different methodologies. The first polarizable water model we developed was a combination of charge response kernel (CRK) method and polarizable point dipole (PPD) method. In the CRK method, a CRK matrix is defined as the second order derivative of energy with respect to the external potential at atomic sites. It is applied to represent the intensity of charge response to external environment. While in the PPD method, the polarizability tensor which is the second order derivative of energy with respect to external field at the same site, is introduced to characterize the variation of dipole moment in the presence of external perturbation. In our method, we proved that although the CRK matrix of three-site water model has 9 element, it only carries two independent variables, and these two variables only rely on the water geometry and the in-plane polarizability. Thus besides the CRK matrix located on each atomic site, an additional polarizability residing on oxygen atom specifically inducing dipole moment along the direction perpendicular to the water plane was added in our model. With the addition of the out-of-plane description, some physical properties were much enhanced. In the second polarizable water model we extended, electronegativity equalization (EE) method was employed. In this three-site water model, atomic electronegativity and hardness matrix were the first and second order derivative of energy with respect to the partial charge on atomic sites, respectively. In this method, electronegativity differs among different atom types, and the off-diagonal elements in hardness matrix are related on not only atom types but also distances among the corresponding atoms. Accordingly, the intramolecular water deformation can be included. Thus flexible polarizable water model is accessible. With flexibility, this water model is more realistic. Our model validated that more flexible parameterization and geometry could improve the physical performance. At last, we connected the second polarizable water model with the first one. Although the two polarizable models were derived from different methodologies, we proved that under one simple approximation, corresponding CRK matrix can be achieved from hardness matrix. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
13

Intermolecular forces and the virial equation of state

Bird, R. Byron January 1950 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1950. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 135-137).
14

Reactive cross sections obtained from total cross section measurements

Field, Jay Ernest, January 1975 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 67-68).
15

Modelling of mass transfer in packing materials with cellular automata /

Engelbrecht, Alma Margaretha. January 2008 (has links)
Thesis (MScEng)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
16

Accurate ab initio intermolecular potentials with a focus on monomer flexibility

Murdachaew, Garold. January 2005 (has links)
Thesis (Ph.D.)--University of Delaware, 2005. / Principal faculty advisor: Krzysztof Szalewicz, Dept. of Physics and Astronomy. Includes bibliographical references.
17

O ensino por investigação abrindo espaços para a argumentação de alunos e professores do ensino médio /

Bianchini, Thiago Bufeli. January 2011 (has links)
Orientador: Silvia Regina Quijadas Ara Zuliani / Banca: Maria Eunice Ribeiro Marcondes / Banca: Odete Pacubi Baierl Teixeira / Resumo: Nas últimas décadas, o Ensino de Ciências vem buscando estratégias que favoreçam o entendimento dos conteúdos científicos ou, como indica Driver (1999), a enculturação da Ciência (DRIVER, CAPECCHI E CARVALHO, MORTIMER, 2000), além da formação de alunos e professores críticos e reflexivos. O uso da argumentação em salas de aula pode se tornar grande aliada na formação de jovens pensadores e críticos, que consigam utilizar seus pensamentos em favor próprio e em conjunto, que sejam capazes de discutir problemas e propor soluções, não apenas na escola, mas em seu dia a dia. Para favorecer a argumentação, foi utilizado um minicurso investigativo com o tema "Forças intermoleculares". Nossa proposta de trabalho procurou investigar quais são as potencialidades do uso integrado desses referenciais teóricos e qual a contribuição de uma proposta de minicurso invesetigativo no desenvolvimento de habilidades de argumentação em alunos e futuros professores além de analisar a proposta investigativa utilizada. Os dados analisados foram divididos em três categorias, i) a proposta do minicurso investigativo com base na classificação de atividades de ensino proposta por Canal (2000), ii) a qualidade da argumentação com Osborne et al (2004) e iii) a atuação do professor na elaboração dos argumentos dos alunos com Mendonça e Justil (2009). Os resultados mostram que a atividade proposta favoreceu a argumetnação dos alunos e professores, possibilitando a abertura de espaços na sala de aula para que ocorra diálogo entre os alunos e os professores. Pode-se perceber o papel fundamental do professor na elaboração dos argumentos dos alunos, pois, se os mesmos não direcionarem as discussões, os argumentos podem ser mal elaborados ou mal explorados / Abstract: In recent decades, the Teaching if Science has been searching for strategies that enhance the understanding of scientific content or, as indicated by Driver (1999), enculturation of Science (DRIVER, Capecchi and CARVALHO, MORTIMER, 2000) and the training of teachers ans students to be critical and reflective. The use of argumentation in the classroom can become a great ally in forming young thinkers and critics, who can use their own behalf and thoughts together; they can discuss problems and propose solutions, not just in shool but in their day by day. To facilitate the argument we used an investigate shor course with the theme "Intermolecular Forces". Our proposal of work aimed to investigate what are the potential use of integrated theoretical and the contribution of a proposed short course in the development of investigate reasoning abilities in students and future teachers as well as used to analyze the research proposal. Data were divided into three categories, i) the proposed investigative mini course based on the classification of educational activities proposed by Canal (2000), ii) the quality of argumentation with Osborne et al (2004) and iii) the performance of teacher in preparing students with the arguments of Mendonça and Justi (2009). The results show that the proposed activity favored the argument of the students and teachers, enabling the opening of spaces in the classroom dialogue to occur between students and teachers. It can be noticed the teqacher's role in the development of students arguments, because if they do not guiding discussions arguments can be poorly designed or poorly explored / Mestre
18

Charge Regulation of a Surface Immersed in an Electrolyte Solution

Unknown Date (has links)
In this thesis, we investigate theoretically a new model of charge regulation of a single charged planar surface immersed in an aqueous electrolyte solution. Assuming that the adsorbed ions are mobile in the charged plane, we formulate a field theory of charge regulation where the numbers of adsorbed ions can be determined consistently by equating the chemical potentials of the adsorbed ions to that of the ions in the bulk. We analyze the mean-field treatment of the model for electrolyte of arbitrary valences, and then beyond, where correlation effects are systematically taken into account in a loop expansion. In particular, we compute exactly various one-loop quantities, including electrostatic potentials, ion distributions, and chemical potentials, not only for symmetric (1, 1) electrolyte but also for asymmetric (2, 1) electrolyte, and make use of these quantities to address charge regulation at the one-loop level. We find that correlation effects give rise to various phase transitions in the adsorption of ions, and present phase diagrams for (1, 1) and (2, 1) electrolytes, whose distinct behaviors suggest that charge regulation, at the one-loop level, is no longer universal but depends crucially on the valency of the ions. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
19

Direct measurement of depletion force between two surfaces with total internal reflection microscopy.

January 2009 (has links)
Xing, Xiaochen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references. / Abstract also in Chinese. / Abstract (Chinese) --- p.i / Abstract --- p.iii / Contents --- p.v / Acknowledgement --- p.ix / Chapter Chapter1 --- Introduction and background / Chapter 1.1 --- Overview of Studies in Colloid-Polymer mixture --- p.1 / Chapter 1.2 --- Depletion Force in Colloid-Polymer Mixture --- p.1 / Chapter 1.2.1. --- Depletion Interaction in Monodisperse and Neutral Polymer-Colloid Mixtures: Theory --- p.3 / Chapter 1.2.1.1. --- An Exact Result: the Interaction between Parallel Plates due to Ideal Polymer Chains --- p.3 / Chapter 1.2.1.2. --- Penetrable Hard Sphere (PHS) Approach --- p.4 / Chapter 1.2.2. --- Early Experimental Findings of Depletion Interaction --- p.6 / Chapter 1.3 --- References and Notes --- p.8 / Chapter Chapter2 --- Principle of Total Internal Reflection Microscopy (TIRM) and Instrumentation / Chapter 2.1 --- Introduction of Total Internal Reflection Microscopy (TIRM) --- p.10 / Chapter 2.2 --- The Principle of TIRM Technique --- p.11 / Chapter 2.2.1 --- Total Internal Reflection --- p.11 / Chapter 2.2.2 --- Details on Scattering of the Evanescent Wave --- p.13 / Chapter 2.2.3 --- Data Analysis --- p.16 / Chapter 2.3 --- Instrumentation --- p.20 / Chapter 2.3.1 --- Apparatus --- p.20 / Chapter 2.3.2 --- Optical Tweezer --- p.23 / Chapter 2.3.3 --- Cleaning of the Slide Surface --- p.24 / Chapter 2.3.4 --- A Typical Potential Energy Profile --- p.25 / Chapter 2.4 --- Laser Light Scattering (LLS) --- p.26 / Chapter 2.5 --- Zeta-potential Measurements --- p.27 / Chapter 2.6 --- References and Notes --- p.28 / Chapter Chapter3 --- Depletion Attraction between a Polystyrene Sphere and a Hydrophilic Surface in a Pluronic Aqueous Solution / Chapter 3.1 --- Introduction --- p.30 / Chapter 3.2 --- Experimental Section --- p.34 / Chapter 3.2.1 --- Sample Preparation --- p.34 / Chapter 3.2.2 --- Total Internal Reflection Microscopy --- p.35 / Chapter 3.2.3 --- Laser Light Scattering --- p.36 / Chapter 3.3 --- Results and Discussion --- p.37 / Chapter 3.4 --- Conclusion --- p.48 / Chapter 3.5 --- References and Notes --- p.50 / Chapter Chapter4 --- pH-Controllable Depletion Attraction Induced by Microgel Particles / Chapter 4.1 --- Introduction --- p.53 / Chapter 4.2 --- Experimental Section --- p.54 / Chapter 4.2.1 --- Sample Preparation --- p.54 / Chapter 4.2.2 --- Total Internal Reflection Microscopy --- p.56 / Chapter 4.3 --- Results and Discussion --- p.58 / Chapter 4.4 --- Conclusion --- p.63 / Chapter 4.5 --- References and Notes --- p.64 / Publication List --- p.65
20

The role of three-body interactions on the equilibrium and non-equilibrium properties of fluids from molecular simulation

Marcelli, Gianluca, g.marcelli@imperial.ac.uk January 2001 (has links)
The aim of this work is to use molecular simulation to investigate the role of three-body interatomic potentials in noble gas systems for two distinct phenomena: phase equilibria and shear flow. In particular we studied the vapour-liquid coexisting phase for pure systems (argon, krypton and xenon) and for an argon-krypton mixture, utilizing the technique called Monte Carlo Gibbs ensemble. We also studied the dependence of the shear viscosity, pressure and energy with the strain rate in planar Couette flow, using a non-equilibrium molecular simulation (NEMD) technique. The results we present in this work demonstrate that three-body interactions play an important role in the overall interatomic interactions of noble gases. This is demonstrated by the good agreement between our simulation results and the experimental data for both equilibrium and non-equilibrium systems. The good results for vapour-liquid coexisting phases encourage performing further computer simulations with realistic potentials. This may improve the prediction of quantities like critical temperature and density, in particular of substances for which these properties are difficult to obtain from experiment. We have demonstrated that use of accurate two- and three-body potentials for shearing liquid argon and xenon displays significant departure from the expected strain rate dependencies of the pressure, energy and shear viscosity. For the first time, the pressure is convincingly observed to vary linearly with an apparent analytic y2 dependence, in contrast to the predicted y3/2 dependence of mode -coupling theory. Our best extrapolation of the zero -shear viscosity for argon gives excellent agreement (within 1%) with the known experimental data. To the best of our knowledge, this the first time that such accuracy has been achieved with NEMD simulations. This encourages performing simulations with accurate potentials for transport properties.

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