Desenvolvimento de sistemas líquido cristalinos contendo Ac-WAhx-KTTKS para o tratamento do envelhecimento cutâneo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Obtenção e avaliação de mutantes de Acidithiobacillus ferrooxidans quanto à capacidade de lixiviar minérios de cobre

Pós-graduação em Biotecnologia - IQ

Synthesis and photocatalytic properties of bismuth titanate with different structures via oxidant peroxo method (OPM)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

TiO2/PDMS nanocomposites for use on self-cleaning surfaces

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo da aplicabilidade do sistema pultrudado de fenólica/fibras de carbono em cabos condutores

Pós-graduação em Engenharia Mecânica - FEG

Propriedades estruturais e espectroscópicas de complexos de difenilfosfinatos dos sistemas ternários 'LA'-'CE'-'EU'/'LA'-CE'-'TB'

Pós-graduação em Química - IQ

Filtros UV na água de abastecimento público na região da bacia hidrográfica tietê-jacaré: desenvolvimento de método, estudo de ocorrência e concentrações ambientais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reassessment of the potential applications of Eu3+-doped Y2O3 photoluminescent material in ceramic powder form

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento e caracterização de formulação cosmética contendo nanopartículas de dióxido de titânio para proteção solar

O protetor solar é um produto extremamente importante para proteger a pele da radiação ultravioleta proveniente do sol e capaz de reduzir a incidência de câncer de pele. Os filtros solares são divididos em orgânicos e inorgânicos e, dentre os inorgânicos, se encontra o TiO2 que atua refletindo, espalhando e absorvendo as radiações UV, além de ser fotoestável e de baixo potencial de irritabilidade dérmica. Neste trabalho foram desenvolvidas formulações cosméticas em forma de gel contendo nanopartículas de dióxido de titânio capazes de agir como fotoprotetores físicos e que mantem a transparência ao serem aplicados sobre uma superfície, como a pele. Foram desenvolvidos xerogéis a base de nanopartículas de TiO2 com tamanho e superfície controlados. A partir dessas nanopartículas foi possível preparar formulações cosméticas contendo nanopartículas redispersas de xerogéis a base de TiO2. Esses sistemas foram avaliados por testes de citotoxicidade e foi obtido um resultado favorável para a continuidade da pesquisa, sugerindo o uso deste material em humanos sem causar danos. Foram feitas as caracterizações físico químicas e estruturais. A análise de FPS indicou amplo espectro da formulação, o potencial zeta mostrou que é possível evitar aglomerações das nanopartículas em pHs utilizados para formulações tópicas, a reologia demonstrou que as formulações apresentam comportamento de recuperação da consistência e organização do material inicial após seu desarranjo durante o cisalhamento. As caracterizações serviram para obter um conhecimento da estrutura química e física das amostras que contém as nanopartículas de dióxido de titânio, para que seja possível fazer uma análise crítica e melhor qualificar o protetor solar desenvolvido.

Biodegradação de filmes de polipropileno (PP), poli (hidroxibutirato-co-valerato) (PHBV) e blenda pré-irradiados com luz UV

This work intends to investigate the biodegradation of the polymers and blend films of polypropylene (PP) and poly(hidroxybutirate-valerate) (PHBV), after UV radiation to facilitate the PP degradation, which is a polymer with long chains difficult to degrade by biological agents present in the environment. This polymer is outstanding by its mechanical properties and versatility of industrial and commercial use and the PHBV by its quick biodegradability in the environment. Blends of these materials could to present a commitment between mechanical properties and biodegradability to execute its function and after the discard to have lesser lifetime in the garbage landfills. Another aspect of this work is the controlling effect of PP on PHBV, influencing its degradation time

Compostos fenólicos de 10 variedades de uva

Phenolic compounds represent one of the main groups of secondary metabolites. Due to their chemical diversity, they have a variety of functions in plants, such as protection against ultraviolet radiation, herbivores and pathogens, and attraction of pollinators or dispersers of fruits and seeds. For human, the phenolic compounds are used like food colorings and flavors and, due to their pharmacological properties, mainly to antioxidant activity, they are associated with several health benefits, such as delay senility, prevention and therapy of cardiovascular diseases and of some cancers. The grapes are considered one of the main source of phenolic compounds and the fruit and its products are consumed in Brazil and worldwide. Considering the phenolic compounds diversity and their different distribution in the grape parts, this work had like aims the extraction, identification and quantification of the main classes of phenolic compounds of 10 grape varieties. The content of total phenols, flavanols and anthocyanins were determined, respectively, according to the Folin-Ciocalteu, DMACA and comparison of pH spectrophotometric methods. The content of total phenols varied from 142.75 + 1.86 to 483.39 + 5.90 mg.L-1 in the peel and from 86.50 + 0.54 to 146.32 + 9.97 mg.L-1 in the pulp. The amount of total flavanols varied from 3.68 + 0.03 to 6.92 + 0.26 mg.L-1 in the peel and from 0.90 + 0.00 to 1.36 + 0.00 mg.L-1 in the pulp. The content of total anthocyanins varied from 7.00 + 0.99 to 406.56 + 39.50 mg.L-1 in the peel and from 2.88 + 0.28 to 46.36 + 1.89 mg.L-1 in the pulp. The phenolic compounds concentration was higher in the peel than in the pulp. The total phenols and anthocyanins varied a lot while the total flavanols were more constant. The flavanols represent the smaller portion of phenolic compounds

Influência do condicionamento ambiental sobre as propriedades viscoelásticas de compósitos aramida/epóxi

The increasing application of structural composites in the aerospace industry is mainly due to its low specific weight coupled with its excellent mechanical properties when in service. As a result of climatic variations that pass the aircraft is of paramount importance to study the influence of weathering on this type of material when subjected to such changes. The purpose of this work is to evaluate the mechanical behavior of specimens of kevlar fiber /epoxy matrix composites, by dynamic mechanical thermal analysis (DMA) and interlaminar shear strength tests (ILSS), after passing through three environmental conditioning: saline fog, hygrothermal and ultraviolet radiation. From the results, we concluded that the laminate was molded supplied homogeneously, not presenting problems such as porosity, delaminations or cracks inside. After a period of 625 hours of exposure to hygrothermal conditioning, we observed a 1,2% maximum of absorption of moisture. Samples subjected to the conditioning by UV irradiation (600 hours) and salt spray showed a reduction of about 24,30% and 32,30%, respectively, on the shear strength (ILSS). In DMA analysis is not observed significant changes on the glass transition temperature. However, when considering the storage modulus of the samples conditioned by UV radiation (1200 hours), salt spray and hygrothermal conditioning there is an increase of 5,34% , 7,19% and 5,57% respectively

Comportamentos, térmico e mecânico, de compósitos de polipropileno e resíduo da hidrólise enzimática do bagaço de cana de açúcar

Pós-graduação em Engenharia Mecânica - FEG

Tetraethylortossilicate plasma thin film with hydrophilic and hydrophobic characteristics: Use on passive mixers

This work aims to obtain plasma thin film composites with hydrophobic/hydrophilic alternated regions, which are useful for the production of miniaturized mixers. These regions were acquired by two different strategies: either the codeposition of TEOS and HFE plasma thin films or the exposition of TEOS plasma films to ultraviolet radiation (UVA and UVC). These films were characterized by several chemical and physical techniques. The refractive indexes vary from 1.4 to 1.7; infrared and photoelectron spectroscopy detect Si-O-Si and CHn species. Silicone-like structures with high or low number of amorphous carbon microparticles and with fluorinated organic clusters were produced. Cluster dimensions were in the 1-5 mm range and they are made of graphite or COF (carbon/oxygen/fluorine) compounds. Scanning electron and optical microscopy showed rough surfaces. Water contact angles were 90º; however, for TEOS films that value changed after 6 hr of UVC exposure. Moreover, after UV exposure, organic polar compounds could be adsorbed in those films and water was not. The passive mixer performance was simulated using the FemLab 3.2® program and was tested with 20 nm thick films on a silicon wafer, showing the capacity of these films to be used in such devices.

Bond strenght of dental adhesive systems irradiated with ionizing irradiation

The aim of the present paper was to determine the effect of different types of ionizing radiation on the bond strength of three different dentin adhesive systems. Materials and Methods: One hundred twenty specimens of 60 human teeth (protocol number: 032/2007) sectioned mesiodistally were divided into 3 groups according to the adhesives systems used: SB (Adper Single Bond Plus), CB (Clearfil SE Bond) and AP (Adper Prompt Self-Etch). The adhesives were applied on dentin and photo-activated using LED (Lec 1000, MMoptics, 1000 mW/cm2). Customized elastomer molds (0.5 mm thickness) with three orifices of 1.2 mm diameter were placed onto the bonding areas and filled with composite resin (Filtek Z-250), which was photoactivated for 20 s. Each group was subdivided into 4 subgroups for application of the different types of ionizing radiation: ultraviolet radiation (UV), diagnostic x-ray radiation (DX), therapeutic x-ray radiation (TX) and without irradiation (control group, CG). Microshear tests were carried out (Instron, model 4411), and afterwards the modes of failure were evaluated by optical and scanning electron microscope and classified using 5 scores: adhesive failure, mixed failures with 3 significance levels, and cohesive failure. The results of the shear bond strength test were submitted to ANOVA with Tukey's test and Dunnett's test, and the data from the failure pattern evaluation were analyzed with the Mann Whitney test (p = 0.05). Results: No change in bond strength of CB and AP was observed after application of the different radiation types, only SB showed increase in bond strength after UV (p = 0.0267) irradiation. The UV also changed the failure patterns of SB (p = 0.0001). Conclusion: The radio-induced changes did not cause degradation of the restorations, which means that they can be exposed to these types of ionizing radiation without weakening the bond strength.