933 resultados para 3-DIMENSIONAL POLYMERS
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
ESR measurements In pressed pellets of
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (μCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core - MAu; zirconia core - MZi) and the quality of the veneer/core interface (complete bonded - MZi; incomplete bonded - MZi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σmax) and von Mises equivalent (σvM) stresses were obtained. The σmax (MPa) for the bonded condition was similar between gold and zirconia cores (MAu, 0.42; MZi, 0.40). The incomplete bonded condition (MZi-NL) raised σmax in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σvM increased up to 270% in the MZi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
We construct composite operators in two-dimensional bosonized QCD, which obey a W∞ algebra, and discuss their relation to analogous objects recently obtained in the fermionic language. A complex algebraic structure is unravelled, supporting the idea that the model is integrable. For singlets we find a mass spectrum obeying the Regge behavior.
Resumo:
An alcohol dehydrogenase (ADH) was purified from dry baker’s yeast. This is a key enzyme of the primary short-chain alcohol metabolism in many organisms. In the present study, the obtained enzymatic preparation of baker’s yeast, containing 2.7 U/mg of ADH, was used in the reactions. The purified extract of the ADH obtained from Fermix commercial dry yeast, presented the highest activity and purification factor when ammonium sulfate was added in the precipitation of protein, in the range 35-60% (w/v). The enzymatic preparation was maintained for 2 months in the lyophilized form at 4ºC (retention of 96.2% of activity) in the presence of 1 mmol/L of sodium azide, and it maintained 47% of activity for 30 days at 30°C in the presence of 15% PEG. The assays of ethanol (detection range 5 mM -150 mM or 2.3 x 10-4 – 6.91 x 10-3g/L) in different samples in alcoholic beverages, presented a maximum deviation of only 2.1%. Assays of recovery of the substrate (99.25%) added in the wine showed that the methodology is viable for this sample type. The standard curve and the analytic curve of this method meet the conditions of precision, sensitivity, simplicity, and low cost, required for a useable analytical method.
Resumo:
The effect of gamma radiation on poly{[2,5-bis(3-(N,N-diethylamino)-1-oxapropyl)-1,4-phenylene]-alt-1,4- phenylene} (PPP); poly{[2,5-bis(3-(N,N-diethylammonium bromide)-1-oxapropyl)-1,4-phenylene]-alt-1,4-phenylene} (PPP-Br); and the polymerized dye poly-1-ethyl-2-[3-(1-ethyl-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)-1-propenyl]- 3,3-dimethyl-3H-indolium perchlorate (Poly-CyC) has been investigated. The stability and response of poly [2-methoxy- 5-(2'- ethyl-hexyloxy)-p-phenylenevinylene] (MEH-PPV) in mixed solutions have also been explored. To this end, samples with concentrations ranging from 0.005 to 0.500 mg/mL were irradiated with a 60Co gamma-ray source at room temperature, using doses up to 1 kGy, and the response was analyzed by UV-Vis spectroscopy. The obtained results reinforce the previously proposed mechanism and suggest that the effect depends on specific structural characteristics of the main chain of the polymers. Moreover, the polymerized dyes display interesting dosimetric properties. Additionally, it has been noted that, contrary to what happens in other solvents, MEH-PPV is degraded in bromoform solution. Protective effects have also been observed for bromoform+toluene mixtures (1:1 vol/vol) and solutions containing molecular dyes. - See more at: http://www.eurekaselect.com/117251/article#sthash.gHFnYvJk.dpuf