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This work aims to evaluate the behavior of the FTO/m-BiVO4 photoanode in different electrolytes, pH, anions and cations, in order to investigate the influence of these parameters on their photoelectrochemical activity. The m-BiVO4 semiconductor was developed by combustion synthesis in solution (SCS) and deposited by dip-coating technique on fluorinated doped tin oxide (FTO) coated glass substrate. The morphological and structural characterization of the film was performed by XRD, UV-Vis and SEM measurements. The evaluation of the photosensitive behavior of the film was made by linear voltammetry and chronoamperometry in the presence of pulsed visible light. After photoelectrochemical parameters optimization, the study of photoelectrocatalysis in glucose degradation was performed. Thus, it was possible to evaluate the efficiency of the film in the photoelectrocatalytic processes, presenting itself as a potential material for such applications.

Made available in DSpace on 2019-10-06T17:07:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-01 Made available in DSpace on 2019-10-06T17:07:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Polymeric matrices containing luminescent particles find many applications like temperature sensor platforms. However, it is important to understand the impact of the particle immobilization on the polymer structural and optical properties in order to optimize its performance. Therefore, in this study, a new luminescent polymeric composite was fabricated by combining poly (vinylidene fluoride) (PVDF), buriti oil (BO) and Eu2O3 particles, evaluating the membrane luminescent properties before and after a cryo-treatment with liquid N2 in order to enhance the Eu(III) emission. Also, the influence of Eu2O3 particles and BO in the polymer structural, thermal, morphological and optical properties was evaluated. The composite membranes with bandgap lying between 5.60 and 5.90 eV were obtained as γ-PVDF phase after being dried at 100 °C, with spheroidal particles connected by necks. The PVDF membranes are very stable till temperatures as high as 370 °C, and the Eu2O3 particle addition increases the membrane thermal stability while the BO decreases the PVDF stability. The cryo-treatment with N2 increases the PVDF crystallinity, leading to the PVDF particles agglomeration. The PVDF/BO/Eu2O3 membrane exhibited the characteristic red emission from Eu(III) along with an unexpected BO emission. Finally, after the cryo-treatment, the Eu3+ emission increases while the BO emission vanishes, and due to this temperature sensitivity, the system shows potential to be applied in temperature sensor platforms. São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences FAPESP: 2012/13876-9 CNPq: 2015/10394-1 CAPES: 2016/20421-9

Made available in DSpace on 2020-12-12T01:21:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-22 The present paper describes the development of a novel photochemiresistor sensor for the determination of chemical oxygen demand (COD). A chemiresistive device was produced by a thin film of the monoclinic phase of bismuth vanadate deposited on an FTO glass surface. The resistive properties of the photosensor were carried out by electrochemical impedance spectroscopy (EIS). The electrical resistance of the platform was dependent on the presence of organic material in aqueous solution and the incidence of light. The decrease in resistance can be explained by considering that by increasing the amount of organic material, the amount of charge transferred to BiVO4 increases, as does the amount of the photogenerated conduction band on the film. This behavior is not observed when carrying out the same measurements in the absence of light. Under the optimal experimental conditions, the linear response of the chemiresistor sensor is between 0.20 and 19.9 mg L-1 COD at a fixed AC frequency of 0.1 Hz. There is a good correlation between the charge transfer resistance and COD concentration in the electrolyte solution. Quantification of COD in waste and lake waters was successfully performed using the novel photochemiresistor sensor. The results achieved in the analysis with the sensor are in accordance with the conventional method. Department of Chemistry and Biochemistry School of Science and Technology Sao Paulo State University (UNESP), Rua Roberto Simonsen, 305 CEP Department of Physics School of Science and Technology São Paulo State University (UNESP) Department of Chemistry and Biochemistry School of Science and Technology Sao Paulo State University (UNESP), Rua Roberto Simonsen, 305 CEP Department of Physics School of Science and Technology São Paulo State University (UNESP)

Made available in DSpace on 2018-12-11T17:37:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Structural, morphological and spectroscopic characterization of the Eu3+-doped Y2(MoO4)3 red phosphor incorporated with Au nanoparticles (Au NPs) synthesized via Pechini's method is reported in the present study. In order to evaluate the Au NPs and Eu3+ ions influence on the molybdate structure, the Y2(MoO4)3, Y2(MoO4)3:Eu3+, Y2(MoO4)3/Au and Y2(MoO4)3:Eu3+/Au samples were produced and fully investigated. All samples obtained at relatively low temperature, i.e., 650 °C, show molybdate as the unique phase with high crystallinity assisted by both Eu3+ ions and Au NPs. Water molecules detected in the molybdate structure probably are distorting MoO4, YO6 and EuO6 polyhedra similarly to the Au NPs incorporated in the same lattice. These Au NPs are spherical-shaped with a diameter near to 46 nm and they are located on the molybdate particle surface. The Eu3+-doped phosphors, with or without the presence of Au NPs, exhibit intense red luminescence characteristic of the Eu3+ ion inserted in low-symmetry sites. However, the Au NPs increase the radiative emission rate and absolute quantum yield of the Eu3+ 5D0 emitter state due to the excitation field enhancement caused by the local surface plasmon resonance absorption effect of gold nanoparticles, which was confirmed by diffuse reflectance measurements. Finally, the Eu3+ quantum efficiency enhancement to 92% played by the gold nanoparticles and the high red color purity qualify the obtained phosphor for photonic applications. São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences FAPESP: 2012/13876-9 FAPESP: 2015/10394-1 FAPESP: 2016/20421-9

Made available in DSpace on 2021-06-25T11:17:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-15 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) In the present study, we report the use of an electrochemical sensor for uric acid using a molecularly imprinted polymer (MIP) as a molecular recognition platform. The MIP was based on an azopolymer electropolymerized in the presence of uric acid used as a template molecule. The azo group of the polymer contributes to the quantifiable redox capacitance of the electrode surface, which can be probed by impedance/capacitance spectroscopy. Thus, the advantage of the developed sensor is its ability to perform direct measurements without a soluble redox probe. The molecularly imprinted polymer can sensitively transduce the recognition and binding of specific analytes by redox capacitance. Through electrochemical impedance spectroscopy (EIS) and electrochemical capacitive spectroscopy (ECS), unusual approaches were able to obtain different analytical curves with distinct characteristics, reaching a limit of detection of 0.160 μmol L−1. Department of Chemistry and Biochemistry School of Science and Technology – Sao Paulo State University (UNESP), Rua Roberto Simonsen 305 Department of Chemistry and Biochemistry School of Science and Technology – Sao Paulo State University (UNESP), Rua Roberto Simonsen 305 FAPESP: 2016/09017-1 CNPq: 301298/2017-3 CAPES: 88882.434480/2019-01

No presente trabalho foi estudado o desenvolvimento de um polímero molecularmente impresso (PMI) baseado no poli(azo-Bismarck Y) para detecção de ácido úrico. O filme PMI foi preparado pela eletropolimerização do monômero Bismarck Brown Y na presença de ácido úrico como molécula molde sobre a superfície do eletrodo de óxido de estanho dopado com flúor (FTO). O sensor PMI-poli(azo-Bismark Y) exibiu boa resposta eletroquímica, alta sensibilidade e seletividade na ligação específica ao ácido úrico. Sob as condições experimentais otimizadas, a resposta voltamétrica do sensor proposto foi linear no intervalo de concentração de 0,20 mmol L-1 a 0,60 mmol L-1, com limite de detecção de 0,17 mmol L−1.

Made available in DSpace on 2018-12-11T17:37:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-15 Made available in DSpace on 2018-12-11T17:37:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-15 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Rare-earth-doped phosphors immobilized in polymeric matrices find many applications like LEDs. However, little emphasis has been paid to the phosphor and plasticizer effect on the polymer structural, morphological and spectroscopic properties, for the development of functional devices. In this study, we are reporting for the first time the use of Buriti Oil (BO), a natural oil, as plasticizer in Ba2SiO4:Eu3+-doped PVDF composites membranes. Both, Buriti oil and phosphor amount were varied in the membrane synthesis. The drying temperature at 60 °C leads to the formation of the α-PVDF and the increase of the amount of BO up to 400 μL decreases the PVDF crystallinity. Furthermore, the BO and phosphor additions increase the membrane thermal stability. Finally, the composite obtained with 10 wt% of Ba2SiO4:Eu3+ shows relative intense red emission with maximum at 612 nm originating from the Eu3+ radiative transitions in Ba2SiO4 lattice, making this composite material a good candidate for optical devices. São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences Universidad de Chile Facultad de Ciencias Departamento de Física, Las Palmeras São Paulo State University (Unesp) School of Technology and Sciences São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences FAPESP: 2012/13876-9 FAPESP: 2015/10394-1 FAPESP: 2016/20421-9 CNPq: 307385/20159

We compared the whole complement of midgut carboxypeptidases from 10 insects pertaining to five orders based on transcriptomes obtained by deep sequencing and biochemical data. Most of the carboxypeptidases were metallocarboxypeptidases from family M14, with carboxypeptidase A (CPA) predominating over carboxypeptidase B (CPB). They were found in all of the insects studied except for the hemipterans and a bruchid beetle. M14 carboxypeptidases were expressed only in the midgut of Spodoptera frugiperda (Lepidoptera). The most expressed CPA from this insect (SfCPA) was cloned, sequenced and expressed as a recombinant enzyme. This enzyme was used to generate antibodies used to demonstrate that SfCPA is secreted by an exocytic route. Serine carboxypeptidases from family S10 were found in all of the insects studied here. In S. frugiperda, they are expressed in all tissues besides the midgut, in accordance with their presumed lysosomal role. In the hemipteran Dysdercus peruvianus, S10 carboxypeptidases are expressed only in midgut, suggesting that they are digestive enzymes. This was confirmed by enzyme assays of midgut contents. Furthermore, the substrate specificity of D. peruvianus S10 carboxypeptidases are predicted to be one CPC (preferring hydrophobic residues) and one CPD (preferring basic residues), thus able to hydrolyse the peptides formed by their digestive cathepsin D and cathepsin L, respectively. The role of S10 carboxypeptidases in bruchid beetles are suggested to be the same as in hemipterans.

The contribution of new materials, involving composites and blends, has been reaching the most varied fields of science, as much of the scientific as technological point of view. This is due to the man's needs in applications, especially in medicine areas. Thus, this work shows the preparation and characterization of poly(vinylidene fluoride) (PVDF) and calcium carbonate (CaCO 3 ) composite films in order to analyse the incorporation of CaCO 3 in PVDF for future application in bony restoration and bony filling. The films were prepared by casting method, where the PVDF pellet shape was dissolved in dimethylacetamide (DMA) and in a separate container CaCO 3 /DMA emulsion was also made. Soon afterwards they were mixed in several proportions 100/00, 95/05, 85/15, 70/30 in weight and left to dry in greenhouse. Homogeneous and flexible films were obtained and structurally characterized by attenuated total reflection infrared spectroscopy (FT-IR/ATR), thermal analyses (DSC, TGA), X-ray diffractometry, optical and scanning electron microscopies. The results showed that the material was a composite with good thermal stability until around 400 °C, the crystallinity of PVDF was non-polar α-phase and the obtained films were porous, being these filled with CaCO 3 .

Neste trabalho apresentamos uma nova classe de vidros de fluoretos de metais pesados (HMF) baseados nos fluoretos de índio (InF3) de composição InSrBaZnGdNa e InSrBaZnGaNa. Realizamos um estudo das propiredades físicas (tais como: índice de refração, temperaturas características e estabilidades) e óticas (absorção, emissão e tempo de vida) de vidros puros e dopados com Nd ou Pr. As propriedades estão comparadas com aquelas dos vidros ZrBaLaAlNa (ZBLAN). A principal característica dos vidros de fluoretos de índios puros é a extensa transmissão no IV (até 8330 nm), maiores que a do ZBLAN (até 6650 nm). Tanto os vidros dopados com Nd como com Pr são materiais promissores para o desenvolvimento de laser com emissões a 1050 e 1320 nm nos vidros de Nd e a 1320 nm no vidro com Pr e amplificadores óticos para telecomunicações na janela ótica centrada a 1300 nm, uma vez que apresentam bandas de emissão a 1315 nm (InSBZnGdN), 1317 nm (InSBZnGdN:Nd) e a 1320 nm (InSBZnGdN:Pr). We present a new class of heavy metals fluoride glasses (HMF) of InSrBaZnGdNa and InSrBaZnGaNa compositions. We have realized a study of the physical properties such as refraction index, characteristic temperatures, stability and optical properties such as absorption, emission, lifetime of pure, Nd or Pr doped glasses. These properties are similar to those obtained for glasses of ZrBaLaAlNa (ZBLAN) composition. The main characteristic of pure indium fluoride glasses is their larger transmission window in the infrared region (8330 nm) compared to ZBLAN composition (6650 nm). Rare earth doped glasses are promising materials for the development of glasses laser with emission in the 1050-1320 nm range (Nd) and 1320 nm (Pr), as well as optical amplifiers for telecommunication in the optical window centered at 1300 nm, as prominent emission bands are located at 1315 nm (InSBZnGdN), 1317 nm (InSBZnGdN:Nd) and 1320 nm (InSBZnGdN:Pr).

Nanostructured KSr 2 Nb 5 O 15 oxide was synthesized by the polymeric precursor method, a chemical synthesis route based on the Pechini’s method. The X-ray diffraction (XRD) pattern of the calcined powder at 1150 °C were performed in the angular range 5 ≤ 2 θ ≤ 120° with a 0.02° step and a fixed counting time of 30 s. The XRD data were analyzed by the Rietveld refinements using the FullProf software. The results showed a tetragonal system with the tetragonal tungsten bronze structure (TTB) type ( a = 12.4585 (2) A and c = 3.9423 (6) A, V = 611,90 (2) A 3 ). In this work, the sites occupancy by the K + and Sr 2+ cations on the TTB type structure were determined. The thermal parameters ( B ) were analyzed.

Fluoroindate glasses doped with Pr3+ or Nd3+ are promising materials for the development of fluoride fibers, amplifiers and lasers. The optical properties of an InF3SrF2ZnF2GdF3NaF composition pure and doped up to 3 mol% have been systematically studied. The extended UV transmission of this glass allows the identification of most of the 8 S → 6 P and 8 S → 6 I transitions of Gd ions. The optical transitions of Pr3+ and Nd3+ have been identified in absorption between 250 and 10 000 nm. Fluorescence and excitation spectra and lifetime have been measured at 300 K. Most of the transitions have been identified.

We present results on the characterization of the Clear-PEM breast imaging scanner. Clear-PEM is a dual-head Positron Emission Mammography scanner using APD-based detector modules that are capable of measuring depth-of-interaction (DOI) with a resolution of 2 mm in LYSO:Ce crystals. The full system comprises 192 detector modules in a total of 6144 LYSO:Ce crystals and 384 32-pixel APD arrays readout by ASICs with 192 input channels, which represents an unprecedented level of integration in APD-based PET systems. The system includes Frontend and Data Acquisition electronics and a robotic gantry for detector placement and rotation. The software implements calibration (energy, time and DOI), normalization and image reconstruction algorithms. In this work, the scanner main technical characteristics, calibration strategies and the spectrometric performance in a clinical environment are presented. Images obtained with point sources and extended uniform sources are also presented. The first commissioning results show 99.7% active channels. After calibration, the dispersion of the channels absolute gain is 15.3%, which demonstrate that despite the large number of channels the system is rather uniform. The mean energy resolution at 511 keV is 15.9% for all channels, and the mean DOI constant is 5.9%/mm, which is consistent with a 2 mm DOI resolution, or better. The coincidence time resolution at 511 keV, for a energy window between 400 and 600 keV, is 5.2 ns FWHM. The image resolution measured with point sources was found to be of the order of 1.3 mm FWHM. The DOI capability was found to have a strong impact on the image sharpness. Images of extended uniform (68)Ge sources, corrected for sensitivity and for the artifacts due detector dead spaces, have good uniformity. First clinical breast images are presented.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:48:48Z No. of bitstreams: 1 S0100-40422009000700004.pdf: 590999 bytes, checksum: 0a58a7ca40ca6f43d14bc6cd492e6f64 (MD5) Made available in DSpace on 2013-08-22T18:48:48Z (GMT). No. of bitstreams: 1 S0100-40422009000700004.pdf: 590999 bytes, checksum: 0a58a7ca40ca6f43d14bc6cd492e6f64 (MD5) Previous issue date: 2009-01-01 Made available in DSpace on 2013-09-30T18:09:33Z (GMT). No. of bitstreams: 2 S0100-40422009000700004.pdf: 590999 bytes, checksum: 0a58a7ca40ca6f43d14bc6cd492e6f64 (MD5) S0100-40422009000700004.pdf.txt: 34392 bytes, checksum: 3907d1c8ee6c6f64101a5a5d4a7f849f (MD5) Previous issue date: 2009-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:23:10Z No. of bitstreams: 2 S0100-40422009000700004.pdf: 590999 bytes, checksum: 0a58a7ca40ca6f43d14bc6cd492e6f64 (MD5) S0100-40422009000700004.pdf.txt: 34392 bytes, checksum: 3907d1c8ee6c6f64101a5a5d4a7f849f (MD5) Made available in DSpace on 2014-05-20T13:23:10Z (GMT). No. of bitstreams: 2 S0100-40422009000700004.pdf: 590999 bytes, checksum: 0a58a7ca40ca6f43d14bc6cd492e6f64 (MD5) S0100-40422009000700004.pdf.txt: 34392 bytes, checksum: 3907d1c8ee6c6f64101a5a5d4a7f849f (MD5) Previous issue date: 2009-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) KSr2Nb5O15 is a ferroelectric material. The sintering process of the KSr2Nb5O15 ceramic doped with different amounts of CuO was investigated in this research. It was found that CuO is effective as promoter of the densification process of the KSN ceramic. The developed microstructures were different due to the amount of CuO and secondary phases were observed in the microstructures. However, the results of X - ray diffraction showed that only the tetragonal tungsten bronze (TTB) structure was identified in all the investigated ceramic systems. The thermal behavior of CuO and also of the CuO - KSN phase mixture was investigated by thermal analysis. Universidade Estadual Paulista Faculdade de Ciências e Tecnologia Departamento de Física, Química e Biologia Universidad de Oriente Facultad de Ingeniería Química Universidade Estadual Paulista Faculdade de Ciências e Tecnologia Departamento de Física, Química e Biologia

UNIV SAO PAULO,INST FIS & QUIM SAO CARLOS,DEPT FIS & CIENCIA MAT,BR-13560 SAO CARLOS,SP,BRAZIL

This work reports on the effects from thermal treatment in poly(vinylidene fluoride), PVDF, obtained with differential scanning calorimetry (DSC) and dynamic thermal analysis (DMA) measurements. It is shown that in successive DMA measurements performed with one sample the a relaxation peak almost disappears while the /spl gamma/ ' peak appears. The /spl alpha/ relaxation peak, at /spl sim/100/spl deg/C in DMA measurements, is attributed to the preferential orientation of chains in the amorphous phase while the /spl gamma/ ' relaxation peak, at /spl sim/50/spl deg/C, is related to the thermal treatment to which the sample was submitted.

No estudo do transporte e armazanamento de cargas elétricas, em filmes de Teflon FEP, utilizamos a Técnica de Pulso Térmico em conjunto com a Técnica de Corrente Termoestimulada em circuito aberto. Através das duas técnicas, pudemos acompanhar a evolução das cargas nas amostras (de 25 &#956m) submetidas ao Annealing e a descarga iônica em diferentes situações, comparando os resultados obtidos em amostras virgens com as amostras tratadas ou irradiadas. No caso das amostras irradiadas, verificamos que o contato era injetor de buracos e, posteriormente, sugerimos a dependência da mobilidade de buracos com o campo elétrico aplicado. Na tentativa de explicar os resultados obtidos, fizemos uso de alguns modelos teóricos de correntes limitadas por carga espacial. The Heat Pulse and TSC (Thermo-Stimulated-Current) in open circuit techniques were used to study the transport and storage of injected charge in Teflon FEP films. Using these techniques it was possible to follow the evolution of the injected charge inside the samples. Virgin samples (as received), previously annealed samples and previously ionic bombarded samples were used. The results of treated samples were compared with the results of virgin samples. Aluminum evaporate contacts covering ionic bombarded surface show hole injection properties. Measurement of space charge limited currents shows a mobility dependent of the electrical field (&#956 &#945 E-1/2).

Samples with a composition of 40InF3–20ZnF2–5MCl–xBaF2–ySrF2, where M=Na, Li and x+y=35 mol%, were prepared. The thermal properties related to the Ba/Sr ratio and to the remaining chlorine content in the glasses were studied. Thermal stability is improved with the addition of chlorine. However, chlorine concentration is regulated by the sublimation of indium fluorides which takes place at about 600°C. Indium fluorides are formed during glass fusion. The mechanisms of chlorine sublimation were studied.

In the text the author presents a differentiated alternative for assistance in the construction of knowledge. Such work was chosen due to the fact that despite 40 years of progress in developing techniques to assist in the cognitive development of the study, many of these techniques are not used. In order to show a possible solution to this problem it was selected a software that allows an optimization of the time required for the presentation of electrodynamics content in a satisfactory and playful way. No texto, o autor apresenta uma alternativa diferenciada para o auxílio na construção do conhecimento. Tal forma de trabalho foi escolhida perante o fato de que, apesar dos 40 anos de avanço no desenvolvimento de técnicas que ajudem no desenvolvimento cognitivo do estudo, muitas destas técnicas não são utilizadas. No intuito de mostrar uma possível solução para tal problema, foi escolhida a utilização de um software que permite uma otimização do tempo necessário para a apresentação do conteúdo de eletrodinâmica de forma satisfatória e lúdica. xi, 42 f

This paper which was developed by Universidade Estadual de Maringá Graduate Program in the course of National Professional Mastership in the Education of Physics (MNPEF), aimed to provide didactic tools for teaching Physics in the electromagnetic wave and polarization light contents, so that they may contribute as a subsidy for high schoolteachers and higher education professors. It was carried out bibliographical research in Physics textbooks as part of the development of the research. This research was done in order to observe how the concepts chosen are approached as well to elaborate didactic simulations using the Mathematica software, with GIF animations of electromagnetic waves propagating through polarizers and optically active means (Educational Product). This Educational Product was applied in the classroom, aiming to understand its use in the students? teaching and learning process, considering the contents involved. From the perspective of the meaningful learning theory of Ausubel, we develop our activities in a class of third year of public high school, having as advanced organizers, the observation with polarizing filters, the observation of a liquid crystal display (LCD) which had its polarizer taken out, an experiment with an optically active solution of sucrose and the use of GIF animations. At the end of each advanced organizer used, each group of students had to describe what they had assimilated of the content transmitted in the classroom. As a final learning activity, it was asked the students to develop a concept map about the assimilated concepts of electromagnetic waves and polarization of light. Our results show that the teaching methods that have been used in class, contributed significantly to the students learning about the content which was taught O presente trabalho, desenvolvido junto ao Programa de Pós-graduação da Universidade Estadual de Maringá no curso de Mestrado Nacional Profissional de Ensino de Física (MNPEF), teve como objetivo disponibilizar ferramentas didáticas para o ensino de Física no conteúdo de onda eletromagnética e polarização da luz que possam contribuir como subsídio para professores do ensino médio e ensino superior. Como parte do desenvolvimento da pesquisa foi realizada pesquisa bibliográfica em livros didáticos de Física, para observação da forma como são abordados os conceitos escolhidos; bem como elaboradas simulações didáticas com o uso do software Mathematica®, com animações GIF de ondas eletromagnéticas se propagando e atravessando polarizadores e meios opticamente ativos (Produto Educacional). O produto educacional produzido foi aplicado em sala de aula, com o intuito de compreender o seu uso no processo de ensino e aprendizagem dos alunos considerando os conteúdos envolvidos. Na perspectiva da teoria da aprendizagem significativa de Ausubel desenvolvemos nossas atividades em uma turma do terceiro ano do ensino médio público; tendo como organizadores prévios a observação com filtros polarizadores, bem como a observação de um monitor de cristal líquido (LCD) que teve seu polarizador de saída retirado, experimento com uma solução opticamente ativa de sacarose e utilização das animações GIF. Ao final de cada organizador prévio utilizado, era solicitado que cada grupo descrevesse o que havia assimilado do conteúdo transmitido em sala, e como atividade final de verificação de aprendizagem pediu-se para cada grupo desenvolver um mapa conceitual sobre os conceitos assimilados sobre ondas eletromagnéticas e polarização da luz. Nossos resultados evidenciam que as metodologias de ensino que foram utilizadas em sala, contribuíram de maneira significativa para o aprendizado do aluno sobre o conteúdo ensinado x, 123 f

Despite the advances of academic research on teaching physics in Brazil, regarding the understanding of the problems related to the teaching of Science and the existence of a disclosure system (journals, events, dissertations, theses, postgraduate courses), there is still little classroom application. These results still find resistance to its application in pedagogical practice, as the actual practice of teachers in the area is still marked by traditional perspectives of teaching and learning, either for material reasons, either by problems in the very formation of the science teacher. Research in Teaching Physics have shown that there are great difficulties that students feel in learning the various contents of physics, as well as apply them in everyday situations. In light of this situation, this paper seeks to attempt to insert primary concepts of electricity in the discipline of physics of elementary school I series. In order to do this, a research was first carried out with students of these series in a private school in Maringá, about their previous knowledge in a certain subject related to Physics, later, it was proposed the use of some electrical instruments for students to try to conceptualize Current and its effects with concrete experimentation. Apesar do grande avanço da pesquisa acadêmica sobre ensino de Física no Brasil, no sentido da compreensão dos problemas relativos ao ensino dessa Ciência e da existência de um sistema de divulgação (periódicos, eventos, dissertações, teses, cursos de pós-graduação), ainda há pouca aplicação desses resultados em sala de aula. Tais resultados ainda encontram resistências à sua aplicação na prática pedagógica, visto que a prática concreta dos professores na área ainda é marcada por perspectivas tradicionais de ensino e aprendizagem, seja por motivos materiais, seja por problemas na própria formação do professor de Ciências. As pesquisas em ensino de Física têm mostrado que são grandes as dificuldades que os estudantes sentem em aprender os diversos conteúdos da Física, bem como em aplicá-los em situações cotidianas. Decorrente disso, o presente trabalho busca a tentativa de inserção de conceitos primários de eletricidade da disciplina de Física nas séries do ensino fundamental I. Para isso foi feito, primeiramente, uma pesquisa com alunos dessas séries em um colégio privado de Maringá, a respeito dos seus conhecimentos prévios em um determinado tema relacionado à Física, posteriormente, foi proposto o uso de alguns instrumentos elétricos para que os alunos tentassem conceituar corrente elétrica e seus efeitos com experimentação concreta. vii, 50 f

Nos últimos anos, acentuou-se o interesse em materiais semicondutores com alto número atômico e alto gap de energia para aplicações na detecção de radiação ionizante à temperatura ambiente, usando o método direto de detecção. Este trabalho apresentara as características de dois materiais semicondutores na forma de filme para o iodeto de chumbo e de cristal milimétrico para o iodeto de mercúrio. Os filmes foram depositados a partir da evaporadora térmica construída no próprio departamento e caracterizados em função de três distâncias de deposição. O melhor filme obtido foi produzido a 5 cm de distância da fonte, apresentando valores de gap de energia de 2,39 eV e energia de ativação de 1,1 eV. Com o aumento dessa distância as propriedades estruturais, ópticas e elétricas se deterioram, inclusive com variação da composição do material. Os cristais de iodeto de mercúrio foram dissolvidos no solvente orgânico N-N Dimetilformamida e crescidos utilizando a técnica de deposição de solvente. Diferentes taxas de crescimento foram usadas para o crescimento dos cristais. Os melhores resultados foram obtidos para crescimento na estufa a 80ºC, produzindo filmes com gap de energia de 2,2 eV e resistividade da ordem de 108 ?.cm, indicando dopagem não intencional ou excesso de defeitos. A composição obtida é de HgI3, e a razão da fotocorrente pela corrente de escuro quando na faixa de raios-X mamográficos é da ordem de 25. Com as otimizações indicadas no texto e na conclusão do trabalho esses materiais seriam fortes candidatos para aplicações comerciais em imagens médicas para energias na faixa mamográfica. In the last years there has been a growing interest in semiconductor materials with high atomic number and optical band gap for applications as ionizing radiation detectors at room temperature, using the direct method of detection. Some materials such as lead iodide (PbI2) and mercury iodide (HgI2) have an optical band gap above 2,0 eV, operate at room temperature with low noise and low leakage current, present a high carrier mobility and high stopping power for ionizing radiation. Alternative methods are investigated by several researchers for the fabrication of these materials on top of large areas, with low fabrication time and costs as desirable for applications in medical imaging. In this sense, we present two methods for the development of the detectors. Thermal evaporation, with the development of the deposition system and chamber, is used for the fabrication of lead iodide thin films. The properties of the films were investigated as a function of deposition height. On the other hand, isothermal evaporation was used for the fabrication of mercury iodide milimetric crystals, for the first time using the organic solvent N.N- dimetilformamide (DMF). The properties of the crystals are investigated as a function of concentration and growth temperature. The structural, morphological and compositional properties of the films and crystals were investigated. The optical and electrical properties were also investigated for both films and crystals. The activation energy for electric transport and the test of the materials as sensors (using X-rays in the mammographic region) were studied. This work presents the main results for both materials: films of lead iodide and milimetric crystals of mercury iodide. The crystalline planes of the films have a preferential orientation along the (110) direction, and a morphology of vertical leaves, not similar to other reported results. The obtained composition is PbI2,5. The combination of the morphology and the configuration of co-planar contacts for charge collection reduce the sensitivity to X-rays exposure. A current density ratio (illuminated to dark) of the order of 1.53 was obtained. The best film was deposited at a distance of 5 cm to the source, and it has an optical gap of 2,39 eV and activation energy of 1,1 eV. With increasing deposition distance a degradation of the structural, optical and electrical properties was observed, even with the variation of the composition of the films. For mercury iodide, for any growth rate the shape of the crystals is always cubic. The morphology of the surface depends on the evaporation rate (it can be smooth or present macroscopic holes). The best results were obtained for a growth at 80o C, what leads to a crystal with optical gap of 2.2 eV and electrical resistivity of the order of 108 Ohmcm, what suggests non-intentional doping or excess of defects. The obtained composition was HgI3, and the current ratio (illuminated by mammographic X-rays to dark) was about 25. According to the discussions in the text and in the conclusions, the suggested optimizations could lead to the development of materials that might be useful for technological applications in medical imaging for the mammographic energy range.