Desenvolvimento de amostras padrão de referência para difratometria

Galvao, Antonio de Sant'Ana

doi:10.11606/d.85.2011.tde-25082011-153452

Cited by 3 publications

(6 citation statements)

References 21 publications

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“…The starting materials were high purity CeO2, Si, Y2O3 and Al2O3 which were heat treated and selected by sieving in order to present high crystallite sizes, negligible microstrains, and particle sizes in the range of 37 to 44 μm, as described in previous works [2][3][4][5]. These SRM samples, named "IPEN-SRM" were analyzed by high-resolution synchrotron diffraction at the Brazilian Synchrotron Laboratory (LNLS -Campinas -Brazil) and at Alba Synchrotron (Barcelona -Spain) and compared to the NIST SRM samples.…”

Section: Methodsmentioning

confidence: 99%

“…Additionally, for size-strain profile analysis a standard material is generally necessary to determine and correct the instrumental broadening. The requirements for these materials, known as standard reference materials (SRM), may vary for each application but, in general, must: be stable with well-defined cell parameters, present intense reflections without overlaps, present large crystallite sizes and negligible microstrains [2]. The SRM's widely used for these applications are the Standard Reference Materials for Powder Diffraction produced and sold by the US National Institute of Standards and Technology -NIST.…”

Section: Introductionmentioning

confidence: 99%

“…The SRM's widely used for these applications are the Standard Reference Materials for Powder Diffraction produced and sold by the US National Institute of Standards and Technology -NIST. However, due to their high prices, some laboratories do not use these standards or produce their own "homemade" standards, usually not certified [2]. In order to provide an alternative to NIST standards we developed a set of SRM samples especially treated in order to present the required properties for a SRM [2].…”

Section: Introductionmentioning

confidence: 99%

“…However, due to their high prices, some laboratories do not use these standards or produce their own "homemade" standards, usually not certified [2]. In order to provide an alternative to NIST standards we developed a set of SRM samples especially treated in order to present the required properties for a SRM [2]. In this work are presented the results for these samples which are compared to the results of NIST SRM's.…”

Section: Introductionmentioning

confidence: 99%

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Synchrotron diffraction characterization of alternative powder diffraction standards

Martinez¹,

Ichikawa²,

Imakuma³

et al. 2014

Anais Do v Encontro Científico De Física Aplicada

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A set of standard reference materials (SRM) for powder diffraction were developed at the Laboratory of Applied Crystallography of the Nuclear and Energy Research Institute -IPEN/CNEN, aiming to offer an alternative to the expensive standards produced and sold by the US National Institute of Standards and Technology -NIST. The materials studied as standards were high purity samples of CeO2, Y2O3, Si and Al2O3 submitted to thermal treatments and careful selection by sieving. These standard materials were characterized by diffraction at two synchrotron sources and were compared to the NIST ones. The results show that the produced SRM's present quality similar or, in some cases, superior to the NIST ones.

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Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Synchrotron diffraction characterization of alternative powder diffraction standards

Martinez¹,

Ichikawa²,

Imakuma³

et al. 2014

Anais Do v Encontro Científico De Física Aplicada

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“…O Y 2 O 3 possui estrutura cristalina cúbica (grupo espacial Ia-3 ) com parâmetro de rede = 10,60Å [55] Neste trabalho este material foi utiizado como padrão para análises microestruturais já que possui tamanho médio de cristalitos grande e nenhuma ou muito pouca microdeformação. O método de preparação deste material padrão foi estudado em detalhes por Galvão [55] e a sua caracterização por Martinez et al [56].…”

Section: 1óxido Deítrio (Y 2 O 3 )unclassified

Aplicações do método Warren-Averbach de análise de perfis de difração

Ichikawa¹

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A Dr.ª Marivone Gusatti e ao Dr. Humberto Gracher Riella da UFSC pelas discussões e amostras de ZnO fornecidas para a realização deste trabalho.Ao grande amigo Doutorando Antonio Carlos Oliveira da Silva do IFUSP pela inestimável ajuda desde os tempos da graduação, pelas conversas, desabafos, risadas e a revisão de parte deste trabalho. ABSTRACTThe objective of this work was to develop and implement a methodology of X-ray Line Profile Analysis (XLPA) for the study and determination of the mean crystallite sizes and microstrains in materials. A computer program was developed to speed up the treatment of diffraction peaks and perform the deconvolution utilizing the Stokes method to correct the instrumental contribution in the X-ray diffraction measurements. The XLPA methods used were the Scherrer, Williamson-Hall and Single-Line methods, which can be called real space methods, and the Fourier space method of Warren-Averbach. Furthermore, considering a mathematical modelling it was possible to calculate the crystallite size distribution, considering the log-normal distribution and spherical crystallites. It was possible to demonstrate the proposed theory can provide reliable results evaluating a dispersion parameter. The methodologies described above were applied in two distinct materials: in the alloy Zircaloy-4 and in ZnO.Keywords: Warren-Averbach method, X-ray line profile analysis, mean crystallite size, microstrain, crystallite size distribution Fourier Analysis.

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>p<Síntese de nanopartículas de Ni/Ni>sub<3>/sub<C via decomposição térmica na presença dos pares ligantes oleilamina/ácido oleico e oleilamina/óleo de palmiste: um estudo comparativo através de técnicas de caracterização convencionais e análise local por espectroscopia de correlação angular γ - γ perturbada>/p<

Silva¹

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Meus sinceros agradecimentos a todos que de alguma forma contribuíram para elaboração deste trabalho. Gostaria de destacar o agradecimento: À minha família, por toda compreensão, carinho e dedicação de uma vida.À minha querida Katiusse Soares, pela cumplicidade, paciência, cuidados, sorrisos, auxílios durante a elaboração deste trabalho e dedicação dos últimos anos. À Dra. Cleidilane Sena pela colaboração, pela obtenção do óleo de palmiste em colaboração com o Laboratório de Extrações (LabEx/UFPA). À Dra. Dolores R.R. Lazzar pelo apoio, incentivo e disponibilidade dos laboratórios e equipamentos do laboratório de Insumos do CECTM.Ao Dr. Artur Carbonari, por toda colaboração, apoio e disponibilidade dos laboratórios do grupo de Interações Hiperfinas do CERPQ para síntese das nanopartículas e caracterizações por espectroscopia CAP, fundamentais para este trabalho.

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Desenvolvimento de amostras padrão de referência para difratometria

Cited by 3 publications

References 21 publications

Synchrotron diffraction characterization of alternative powder diffraction standards

Synchrotron diffraction characterization of alternative powder diffraction standards

Aplicações do método Warren-Averbach de análise de perfis de difração

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