Synthesis and characterization of cross-linked molecularly imprinted polyacrylamide for the extraction/preconcentration of glyphosate and aminomethylphosphonic acid from water samples

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Moments of induced spawning and embryonic development of Brycon amazonicus (Teleostei, Characidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Preparação de substratos de carbeto de silício para fins aeroespaciais

This conclusion thesis has the objective of produce substrates of Silicon Carbide from the powder of SiC for aerospace use. The powder of SiC was pressed in cylindrical form by the process called “wet way”. For the inicial pressing process was used a uniaxial squeezer and after that was used a isostatic squeezer, after that the samples were synthesized. The next step was the machining and polishing to improve the features of the surface of the sample. Then the roughness was measured, as also the Arquimedes method and optical microscopy and scanning eletron microscopy. Some innovations were done, in one of the lots little vacancys were done with organic material or silicon to reduce the weight of the sample; and the other innovation were the use of a slip film of SiC on the surface of the sample, that were after synthesized with LASER to reduce the roughness, in this samples the roughness were reduce in 50 % if compared with the other samples

Sintese e caracterização do compósito TixOy- MWCNT para fotodegradação de carbaril

In this study, a composite of titanium oxide (TixOy) and carbon nanotubes multi-walled (MWCNT) was synthesized on a titanium substrate using the sol-gel method. The electrode obtained (TixOy-MWCNT/Ti) was used to the photodegradation of Carbaryl. The morphology and structure of the TixOy-MWCNT composite were characterized by scanning electron microscopy (SEM), scanning electron microscopy by field emission (FEG-SEM) and X-ray diffraction (XRD). The electrode was evaluated for degradation of Carbaryl (0.9 mmol L-1) in phosphate buffer pH 6, and using chronoamperometry by applying a potential of +1,5 V for 1 h. Using the Ultraviolet-Visible test, the absorbance at 220 nm was collected every 15 min to calculate the percentage of Cabaryl´s degradation. Can be evaluated that the Carbaryl degradation using the TixOy-MWCNT/Ti electrode was 22% more efficient when compared with the electrode without the presence of titanium oxides (MWCNT / Ti)

Uso de cascas de laranja como adsorvente de contaminantes no tratamento de água

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

Chitosan-collagen scaffolds can regulate the biological activities of adipose mesenchymal stem cells for tissue engineering

Scaffolds of chitosan and collagen can offer a biological niche for the growth of adipose derived stem cells (ADSC). The objective of this work was to characterize the physico-chemical properties of the scaffolds and the ADSC, as well as their interactions to direct influences of the scaffolds on the behavior of ADSC. The methodology included an enzymatic treatment of fat obtained by liposuction by collagenase, ASDC immunophenotyping, cell growth kinetics, biocompatibility studies of the scaffolds analyzed by the activity of alkaline phosphatase (AP), nitric oxide (NO) determination by the Griess-Saltzman reaction, and images of both optical and scanning electron microscopy of the matrices. The extent of the crosslinking of genipin and glutaraldehyde was evaluated by ninhydrin assays, solubility tests and degradation of the matrices. The results showed that the matrices are biocompatible, exhibit physical and chemical properties needed to house cells in vivo and are strong stimulators of signaling proteins (AP) and other molecules (NO) which are important in tissue healing. Therefore, the matrices provide a biological niche for ADSC adhesion, proliferation and cells activities.

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

SnO2 dense ceramic microwave sintered with low resistivity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Synthesis and preliminary characterization of Poly(Propylene)Imine hexadecylamine dendrimer (DAB-Am-16) modified with methyl acrylate

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

Preparação de nanofio via deposição eletroquímica utilizando modelo de membrana porosa

From the last decade of the twentieth century, the rapid growth of nanotechnology has resulted in the discovery of a number of forms of nanoparticles and nanoclusters. We can cite as an example: nanotubes, nanowires, nanobelts, and nanoconesnanoclusters which have a wide range of applications, particularly as catalysts magnetic material nanodevices, chemical sensors, degradation of toxic chemicals, or even as possible carriers for the isotope medical applications.. The first step is the production and characterization of nanowires multithreaded using different types of metals (nickel, silver, gold) and polymers (pyrrole), which are prepared by electrochemical deposition process. Will be held by the characterization of the same images of scanning electron microscopy (SEM) and transmission electron microscopy (TEM)

The effect of final irrigation on the penetrability of an epoxy resin-based sealer into dentinal tubules: a confocal microscopy study

Introduction The aim of this study was to compare the effect of QMix, BioPure MTAD, 17 % EDTA, and saline on the penetrability of a resin-based sealer into dentinal tubules using a confocal laser scanning microscope (CLSM) and to describe the cleaning of root canal walls by SEM. Methods Eighty distobuccal roots from upper molars were selected and randomly divided into four groups (n=20) before root canal preparation according to the solution used in the final rinse protocol (FRP): QG (QMix), MG (BioPure MTAD), EG (17 % EDTA), and CG (control group: saline). Ten roots of each group were prepared for SEM, and images (×2000) from the canal walls were acquired. The remaining canals were filled with a single gutta-percha cone and AH Plus with 0.1 % Rhodamine B. The specimens were horizontally sectioned at 4 mm from the apex, and the slices were analyzed in CLSM (×10). Sealer penetration was analyzed with Adobe Photoshop software. Results QG and EG presented similar amounts of sealer penetration (P>.05). MG and CG presented the lowest penetrability values (P<.05). The best results for smear layer removal of the apical third of the root canal were achieved by the QG and EG groups when compared with MG and CG (P<.05). Conclusions Seventeen percent EDTA and QMix promoted sealer penetration superior to that achieved by BioPure MTAD and saline. Clinical relevance Despite studies have not confirmed the relationship between sealing ability of endodontic sealers and their penetration in dentinal tubules, sealer penetration assumes importance, since endodontic sealers, unlike guttapercha, are able to penetrate in dentinal tubules, isthmus, and accessory canals, filling the root canal system.

Roughness and morphology of composites: influence of type of material, fluoride solution, and time

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effects of immersion media and repolishing on color stability and superficial morphology of nanofilled composite resin

This study evaluated the influence of fluoride mouth rinses and repolishing on the superficial morphology and color stability of nanofilled resin. About 150 specimens were prepared and polished using aluminum oxide discs for 15 s with a pressure of 2 kg. The experimental groups were divided according to the immersion medium (artificial saliva, 0.5% sodium fluoride, Fluordent Reach, Oral B, Fluorgard) and repolishing procedure (without and with). The specimens were continuously immersed for 1 week. Thereafter, half of each sample was repolished. A color reading was performed after 24 h of immersion in the artificial saliva baseline, after continuous immersion, and after repolishing. The superficial morphology was examined using scanning electron microscopy (SEM) in a qualitative way. Color change (∆E) data were submitted to a mixed analysis of variance using a Shapiro-Wilk test (p>0.05 for the different immersion media) and Sidak's test (p<0.05 for the differences between groups). In the interaction between the repolishing and the immersion media, Fluorgard showed a statistical difference between the ∆E values with and without repolishing (p<0.0001). On the SEM observations, both Fluordent Reach and Fluorgard caused degradation of the superficial resinous matrix of the composite after continuous immersion. This matrix was removed after repolishing.

Avaliação do uso de Selante de Fibrina derivado do veneno de serpente como arcabouço biológico de células tronco mesenquimais na regeneração óssea do fêmur de ratos

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

Tratamento térmico de filmes supercondutores do sistema BSCCO utilizando forno de micro-ondas doméstico

Pós-graduação em Ciência dos Materiais - FEIS