Abstract The objective is to evaluate the effect of different surface treatments and storage on the shear strength of ultratranslucent zirconia. 36 blocks of ultra-translucent zirconia were fabricated (7x7x2mm) and sintered. Then, divided into 12 groups according to the “surface treatment” (C -Primer; Al -Sandblasting with Al2O3 + Primer; Si -Silicate + Primer; Gl -Glaze + HF + Primer; Z -Zirlink; Zp -Zirlink + Primer) and “storage” factors (ST-with 150 days/37º and without). After surface treatment, five cylinders (Ø=2mm; h=2.0mm) of resin cement (n=15) were constructed in each ceramic block; at the end, the shear strength test was performed (1mm/min, 50Kgf), and analysis of surface failures. 60 additional samples (2x2x2mm) were made for extras analysis (surface roughness, MEV, and EDS). Bond strength and surface roughness data were statistically evaluated by ANOVA (2 factors/1 factor), Tukey test (5%), and Weibull analysis, respectively. ANOVA (2-way) revealed that all factors were statistically significant for bond strength. The silicatization groups (SiST: 30.47AMPa; Si: 29.21AMPa) showed the highest bond strength values, regardless of storage (Tukey's test). While the groups treated with Zirlink (ZST: 2.76FMPa; Z: 5.27EFMPa) showed the lowest values, just similar to the GlST group (5.14EFMPa). The Weibull modulus (m) showed a statistical difference between groups (p=0.000). ANOVA (1 factor) revealed that the "surface treatment" factor (p=0.0000) was statistically significant for surface roughness. Therefore, the application of Zirlink and Glaze on pre-sintered zirconia did not promote efficient adhesion of the ultratranslucent zirconia to the resin cement, even when associated with a primer containing MDP. 3 ultra translucent 7x7x2mm xxmm x mm (7x7x2mm sintered Then 1 treatment C Primer -Primer Sandblasting AlO O Al2O Silicate “storage STwith ST 15 days37º daysº days 37º º without. without . without) Ø=2mm Ø2mm Ømm Ø 2mm (Ø=2mm h=2.0mm h20mm hmm h 2 0mm n=15 n15 n (n=15 block end 1mm/min, 1mmmin mmmin 1mm min (1mm/min 50Kgf, 50Kgf Kgf , 50Kgf) failures 6 2x2x2mm (2x2x2mm MEV EDS. EDS EDS) ( factors1 factors/ factor, 5%, 5 5% (5%) respectively 2way way (2-way SiST (SiST 30.47AMPa 3047AMPa AMPa 30 47AMPa 29.21AMPa 2921AMPa 29 21AMPa values Tukeys s test. test) ZST (ZST 2.76FMPa 276FMPa FMPa 76FMPa 5.27EFMPa 527EFMPa EFMPa 27EFMPa 5.14EFMPa. 514EFMPa 5.14EFMPa 14EFMPa (5.14EFMPa) m (m p=0.000. p0000 p p=0.000 0 000 (p=0.000) p=0.0000 p00000 0000 (p=0.0000 Therefore presintered pre MDP n=1 n1 (n=1 1mm/min (5% (5.14EFMPa p000 p=0.00 00 (p=0.000 n= (n= (5 p00 p=0.0 (p=0.00 (n p0 p=0. (p=0.0 p=0 (p=0. p= (p=0 (p= (p

Resumo O objetivo é avaliar o efeito de diferentes tratamentos superficiais e do envelhecimento na resistência ao cisalhamento da zircônia ultratranslúcida. Foram confeccionados 36 blocos de zircônia ultratranslúcida (7x7x2mm) e sinterizados. Em seguida, divididos em 12 grupos de acordo com o “tratamento de superfície” (C-Primer; Al-Jateamento com Al2O3+Primer; Si-Silicato+Primer; Gl -Glaze+HF+Primer; Z-Zirlink; Zp-Zirlink+Primer) e fatores de “armazenamento” (ST-com, 150 dias/37º e sem). Após o tratamento superficial, foram construídos cinco cilindros (Ø=2mm; h=2,0mm) de cimento resinoso (n=15) em cada bloco cerâmico; ao final foi realizado o ensaio de resistência ao cisalhamento (1mm/min, 50Kgf) e análise de falhas superficiais. Foram confeccionadas 60 amostras adicionais (2x2x2mm) para análises extras (rugosidade superficial, MEV e EDS). Os dados de resistência de união e rugosidade superficial foram avaliados estatisticamente por ANOVA (2 fatores/1fator), teste de Tukey (5%) e análise de Weibull, respectivamente. ANOVA (2 fatores) revelou que todos os fatores foram estatisticamente significativos para a resistência de união. Os grupos de silicatização (SiST: 30,47AMPa; Si: 29,21AMPa) apresentaram os maiores valores de resistência de união, independente do armazenamento (Tukey). Enquanto os grupos tratados com Zirlink (ZST: 2,76FMPa; Z: 5,27EFMPa) apresentaram os valores mais baixos, apenas semelhantes ao grupo GlST (5,14EFMPa). O módulo de Weibull (m) apresentou diferença estatística entre os grupos (p=0,000). A ANOVA (1 fator) revelou que o fator “tratamento superficial” (p=0,0000) foi estatisticamente significativo para rugosidade superficial. Portanto, a aplicação de Zirlink e do Glaze na zircônia pré-sinterizada não promoveu adesão eficiente da zircônia ultratranslúcida ao cimento resinoso, mesmo quando associada a primer contendo MDP. 3 7x7x2mm xxmm x mm (7x7x2mm sinterizados seguida 1 superfície CPrimer C Primer (C-Primer AlJateamento Al Jateamento Al2O3+Primer Al2O3Primer AlOPrimer Al2O3 SiSilicato+Primer SiSilicatoPrimer Si Silicato+Primer Silicato Si-Silicato+Primer Glaze+HF+Primer GlazeHFPrimer HF -Glaze+HF+Primer ZZirlink Z Z-Zirlink ZpZirlink+Primer ZpZirlinkPrimer Zp Zirlink+Primer Zp-Zirlink+Primer “armazenamento STcom, STcom ST com, (ST-com 15 dias37º diasº dias 37º º sem. sem . sem) Ø=2mm Ø2mm Ømm Ø 2mm (Ø=2mm h=2,0mm h20mm hmm h 2 0mm n=15 n15 n (n=15 cerâmico 1mm/min, 1mmmin mmmin 1mm min (1mm/min 50Kgf Kgf 6 2x2x2mm (2x2x2mm EDS. EDS EDS) ( fatores/1fator, fatores1fator fatoresfator fatores/1fator , 1fator fatores/1fator) 5% 5 (5% respectivamente SiST (SiST 30,47AMPa 3047AMPa AMPa 30 47AMPa 29,21AMPa 2921AMPa 29 21AMPa Tukey. (Tukey) ZST (ZST 2,76FMPa 276FMPa FMPa 76FMPa 5,27EFMPa 527EFMPa EFMPa 27EFMPa baixos 5,14EFMPa. 514EFMPa 5,14EFMPa 14EFMPa (5,14EFMPa) m (m p=0,000. p0000 p p=0,000 0 000 (p=0,000) p=0,0000 p00000 0000 (p=0,0000 Portanto présinterizada pré sinterizada MDP AlO Al2O SiSilicato SilicatoPrimer ZpZirlink ZirlinkPrimer n=1 n1 (n=1 1mm/min (5 (Tukey (5,14EFMPa p000 p=0,00 00 (p=0,000 n= (n= p00 p=0,0 (p=0,00 (n p0 p=0, (p=0,0 p=0 (p=0, p= (p=0 (p= (p

ABSTRACT Additive manufacturing opens new possibilities for new designs and manufacture of architected metamaterials and nanocomposites. Among the 3D printing technology, vat polymerization is highlighted due its higher resolution, smother surface and printing speed. In spite of the growing interest in the Additive Manufacturing technologies and the potential benefits of graphene reinforcement to improve the properties of parts produced by vat polymerization-based 3D Printing; there is a lack in understanding of the effects of adding graphene to photosensitive vat resin. Therefore, in this study the effect of adding graphene (0.3 and 0.5%) on the chemical, thermal and mechanical properties of parts fabricated by vat polymerization of a standard photosensitive acrylic resin was determined. Graphene addition resulted in a minimal modification of polymeric structure; however, it had a significant impact in the UV curing. The addition of graphene nanoplatelets hindered the photopolymerization of standard acrylic resin as consequence a higher amount of unpolymerized monomers are found after printing. Regarding the mechanical properties, graphene addition promoted a slight improvement in the Elastic Modulus while decreased tensile and flexural strength and it had no significative impact in toughness. An additional thermal curing step can be an alternative to improve polymerization and mechanical strength. These findings contribute to a deeper understanding of the effects of adding graphene to vat polymerization and its potential and limitations. nanocomposites D technology resolution speed polymerizationbased based Printing Therefore 0.3 03 0 3 (0. 0.5% 05 5 chemical determined structure however toughness limitations 0. (0 0.5 (

Abstract Piper nigrum (black pepper) is used in Indian traditional medicine and its main alkaloid, Piperine (PIP), presents antioxidant, antitumor and neuroprotective pharmacological properties. This substance is insoluble in aqueous media and can irritate the gastrointestinal tract. Aiming to avoid these inconvenient characteristics and enable PIP oral administration, this study suggested the PIP microencapsulation through the emulsion-solvent evaporation method and the preparation of microparticulated tablets by direct compression. An UV-spectroscopy method was validated to quantify PIP. Microparticles and microparticulated tablets were successfully obtained and the microparticles exhibited excellent flow. The scanning electron microscopy images showed that PIP microparticles were intact after compression. The in vitro release showed a controlled release of PIP from microparticles and PIP microparticles from tablets in comparison to PIP and PIP tablets. The release profiles of PIP microparticles and the microparticulated tablets were similar. Therefore, tablets containing PIP microparticles are promising multiparticulated dosage forms because a tablet allows microparticles administration and the intact ones promote a controlled release, decreasing its irritating potential on the mucosa. black pepper alkaloid PIP, , (PIP) antioxidant properties tract emulsionsolvent emulsion solvent compression UVspectroscopy UV spectroscopy flow similar Therefore mucosa (PIP

RESUMO Processos assistidos por plasma tem diversas aplicações industrias como a nitretação de aços, sinterização, deposição de filmes finos e produção de semicondutores. A taxa de aquecimento, transferência de calor e temperatura têm um papel fundamental nas propriedades dos materiais imersos em um plasma. Contudo, um dos desafios do processamento de materiais por plasma é medir com precisão a transferência de calor e a temperatura, particularmente em regiões especificas da amostra, uma vez que pode haver a presença picos térmicos, aumentando localmente a temperatura. Além disso, há diversos parâmetros como a composição da atmosfera, potência, pressão e a composição da amostra que podem afetar a difusão, o transporte de massa e a taxa de aquecimento no plasma. Neste contexto, o objetivo deste estudo é avaliar a homogeneidade do aquecimento de amostras de aços revenidas em plasma de argônio e comparar com o aquecimento em forno resistivo. Para este propósito, a microestrutura e a dureza de amostras revenidas em plasma foram comparadas às amostras revenidas em forno resistivo. Desse modo, foi possível determinar a temperatura equivalente de um sólido imerso em plasma. Tendo em vista o grande interesse industrial em processos de nitretação a plasma, neste estudo o aquecimento de amostras de aços imersas em plasma foi avaliado em um reator típico de nitretação a plasma. Para tal, amostras de aço SAE 1045 e 8640 foram temperadas e em seguida revenidas em plasma. As amostras revenidas em plasma mostraram uma maior perda de dureza para o tratamento na mesma temperatura (medida no porta-amostra) do que as amostras revenidas convencionalmente. Este resultado foi relacionado aos picos térmicos durante o aquecimento a plasma. Um modelo matemático para determinar a temperatura equivalente durante o revenimento a plasma foi proposto. Este modelo poderá ser aplicado para desenvolver estratégias para otimizar os parâmetros do plasma, visando melhorar as propriedades dos materiais.

ABSTRACT Plasma-assisted processes have several industrial applications such as steel nitriding, sintering, thin film deposition and semiconductor production. Heating rate, heat transfer and temperature play a key role in the properties of materials immersed in a plasma. However, one of the challenges of plasma processing of materials it is to accurately measure the heat transfer and the temperature, particularly in a specific region of the sample, as there may be thermal spikes, raising locally the temperature. Furthermore, there are several parameters such as plasma atmosphere composition, power, pressure and sample composition that can affect diffusion, mass transport and plasma heating rate. Thus, the aim of this study is to evaluate the heating homogeneity of tempered steel samples in argon plasma and compare it to heating in a resistive furnace. For this purpose, microstructure and hardness of plasma tempered samples were compared to samples conventionally tempered in a resistive furnace, so that the equivalent temperature of a solid immersed in a plasma could be determined. In view of the great industrial interest on plasma nitring process, in this study the heating of steel samples immersed in plasma in a typical plasma nitriding chamber was evaluated. For that samples made of SAE 1045 and SAE 8640 steel were quenched and then tempered in plasma. The plasma tempered samples showed a much smaller hardness for treatment at same measured temperature than conventionally tempered samples. This result was related to thermal spikes during plasma heating. A mathematical model to set the equivalent temperature during plasma tempering was proposed. From this model it is expected to develop strategies to optimize plasma parameters, aiming on improving materials properties.

Cathodic cage discharge was developed recently in order to eliminate phenomena as edge effect and overheating, which occurs during conventional processes. In this study, the effect of cage configuration in active species during the deposition process and optical properties of TiN film were studied. TiN compound was chosen because its optical properties are very sensitive to slight variations in microstructure and film thickness, becoming a good monitoring tool in fabrication process control. Cages were made of titanium and have different holes numbers and holes diameter. Electrical efficiency of the system and optical properties of TiN films were strongly influenced by experimental conditions. It was found that with more holes at the top of cage, deposition rate and crystallinity were higher, if compared to cages with a small number of holes at the top. On the other hand, the opposite behavior was observed when more holes were located at the sidewall of cage.