The fundamental parameters approach is used to simulate the instrument contribution to the X-Ray diffraction profile. This procedure eliminates the need to experimentally prepare a reference sample of the studied crystalline material when using the Warren-Averbach method to investigate microstrutural parameters. The Warren-Averbach method is also compared to the Balzar and Enzo methods, two other popular methods of size-strain analysis. The analysis was carried out using bohmite powder having two different nominal average crystallite sizes, 80 Å and 200 Å. A 50%-50% mixture of these materials was used as a third sample. The proposed simulation procedure provides good results and is much faster to implement than the usual procedure that includes the preparation of a reference. For larger crystallite sizes, the results calculated from the Warren-Averbach method for the volume-weighted average crystallite size differs significantly from the ones obtained from the Balzar and Enzo methods. The limitations of the Balzar and Enzo methods are also discussed

This work studies the crystallinity and rheology of HDPE/PA12 blends compatibilized with 2 wt% of HDPE‐alt‐MAH. Specimens of HDPE/PA12 blends were extruded and injected into a mold with 75/25, 50/50, and 25/75 HDPE/PA ratios. The Fourier‐transform infrared spectroscopy (FTIR) analysis showed that no oxidation reaction occurred in the high‐temperature processing and that stronger interactions between the components of the blends occurred in the polyamide's functional groups. The x‐ray diffraction (XRD) analysis showed that the crystallinity degree of the blends and the mean crystallite sizes decreased with the addition of PA12 for both blends. The HDPE's lattice parameters were consistent with the values in the literature, whereas for the PA12, it was not possible to fit its lattice parameters. The rheology analysis evaluated the relationship between the shear stress and viscosity and found that the HDPE/PA 75/25 blend was the most pseudoplastic, presenting the best processability under high shear rates.

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RESUMOEste trabalho compara as propriedades de diversos óxidos transparentes condutores para serem utilizados como contatos frontais de células solares de filmes finos de CdTe. Os filmes foram depositados à temperatura ambiente, por pulverização catódica com rádio frequência, sem tratamento térmico posterior, com o objetivo de reduzir o número de etapas do processo de fabricação. A relação resistência/transmitância foi avaliada através de uma figura de mérito, de forma a propor os materiais candidatos a atuar como eletrodo frontal da célula solar. Os óxidos investigados foram divididos em dois grupos: os de baixa resistividade e os de alta resistividade. Eletrodos fabricados com os diversos óxidos foram submetidos a testes de estabilidade térmica nas temperaturas de processamento da célula solar. Os resultados mostraram que os filmes de ZnO e Zn 2 SnO 4 são óxidos de alta resistividade (> 0,5 .cm), enquanto que os de SnO 2 , In 2 O 3 , In 2 O 3 :Sn, Cd 2 SnO 4 e ZnO:Al são de baixa resistividade (< 5,0 x 10 -3 .cm) e alta transmitância (> 85%). Os filmes de In 2 O 3 :Sn e ZnO:Al apresentaram-se como as melhores opções para fabricação dos eletrodos, pois possuem resistividades na faixa de 10 -3 -10 -4 .cm e transmitâncias entre 85-92%. No entanto, levando-se em consideração questões de custo e escassez associadas ao índio, filmes de ZnO:Al são os mais adequados para esta aplicação, pois além de possuírem valores de condutividade e transmitância elevados, apresentaram elevada estabilidade térmica nas temperaturas de processamento da célula. Palavras-chave: óxidos transparentes condutores; eletrodos transparentes; células solares; filmes finos ABSTRACT This work compares the properties of different transparent conducting oxides for use as frontal contact in CdTe thin films solar cells. The films were deposited at room temperature by radio frequency sputtering without heat treatment, in order to reduce the manufacturing process steps. The resistance/transmittance relation was evaluated using a figure of merit, in order to propose the best material to act as front electrode of the solar cell. The oxides investigated in this work were separated into two groups: low-resistivity and highresistivity oxides. Electrodes were prepared with these oxides and were subjected to thermal stability tests at the elevated temperatures involved in the solar cell processing. The results showed that ZnO and Zn 2 SnO 4 films are high-resistivity oxides (> 0,5 .cm), while SnO 2 , In 2 O 3 , In 2 O 3 :Sn, Cd 2 SnO 4 , and ZnO:Al are lowresistivity (< 5,0 x 10 -3 .cm) and high transmittance (> 85%) oxides. The In 2 O 3 :Sn and ZnO:Al films were the best options for the production of the electrodes, as their resistivity and transmittance values ranged from

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