Uso da padronização interna em espectrometria de absorção atômica em forno de grafite na determinação de 'SE' e 'NI' em bebidas não alcoólicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da utilização de biomassa em substituição parcial ao carvão mineral utilizado no processo de fabricação do ferro gusa em alto-forno

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise teórica e experimental sobre incandescência em espécimes de madeira

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

Análise do escoamento turbulento por um queimador industrial a gás utilizando dinâmica dos fluidos computacional

Pós-graduação em Engenharia Mecânica - FEG

Preparação e caracterização de ligas do sistema Ti-Mo contendo oxigênio intersticial para aplicações biomédicas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da pressão na obtenção e nas propriedades óticas e sensoras de filmes finos à base de 'SN''O IND. 2' com a adição de 'ZNO'

Pós-graduação em Química - IQ

Estudo metaloproteômico do mércurio em amostras de tecido hepático de peixes coletados na área de influência do AHE JIRAU - Bacia do rio Madeira

Pós-graduação em Biologia Geral e Aplicada - IBB

Aplicação de corretivos de acidez do solo na implantação do sistema plantio direto

Pós-graduação em Agronomia (Agricultura) - FCA

Estudo de geopolímeros utilizando cinzas residuais do bagaço de cana-de-açúcar

Pós-graduação em Engenharia Civil - FEIS

Numerical modeling of flow through an industrial burner orifice

This paper presents numerical modeling of a turbulent natural gas flow through a non-premixed industrial burner of a slab reheating furnace. The furnace is equipped with diffusion side swirl burners capable of utilizing natural gas or coke oven gas alternatively through the same nozzles. The study is focused on one of the burners of the preheating zone. Computational Fluid Dynamics simulation has been used to predict the burner orifice turbulent flow. Flow rate and pressure at burner upstream were validated by experimental measurements. The outcomes of the numerical modeling are analyzed for the different turbulence models in terms of pressure drop, velocity profiles, and orifice discharge coefficient. The standard, RNG, and Realizable k-epsilon models and Reynolds Stress Model (RSM) have been used. The main purpose of the numerical investigation is to determine the turbulence model that more consistently reproduces the experimental results of the flow through an industrial non-premixed burner orifice. The comparisons between simulations indicate that all the models tested satisfactorily and represent the experimental conditions. However, the Realizable k-epsilon model seems to be the most appropriate turbulence model, since it provides results that are quite similar to the RSM and RNG k-epsilon models, requiring only slightly more computational power than the standard k-epsilon model. (C) 2014 Elsevier Ltd. All rights reserved.

Can Heat Treatment Procedures of Pre-hydrolyzed Silane Replace Hydrofluoric Acid in the Adhesion of Resin Cement to Feldspathic Ceramic?

Purpose: To evaluate the influence of heat treatment (HT) procedures of a pre-hydrolyzed silane on bond strength of resin cement to a feldspathic ceramic.Materials and Methods: Ceramic and composite blocks (N = 30) were divided into six groups (n = 5) and subjected to the following conditioning procedures: G1: 9.6% hydrofluoric acid (HF) for 20 s + silane (RelyX Ceramic Primer, 3M ESPE) + resin cement (Panavia F2.0, Kuraray) (control); G2: HF (20 s) + silane + heat treatment in furnace (HTF) (100 degrees C, 2 min) + resin cement; G3: silane + HTF + resin cement; G4-HF (20 s) + silane + heat treatment with hot air (HTA) (50 +/- 5 degrees C for 1 min) + resin cement; G5: silane + HTA + resin cement; G6: silane + resin cement. The microtensile bond strength (MTBS) test was performed using a universal testing machine (1 mm/min). After debonding, the substrate and adherent surfaces were analyzed using a stereomicroscope and SEM to categorize the failure types. The data were statistically evaluated using one-way ANOVA and Tukey's test (5%).Results: The control group (G1) showed no pre-test failures and presented significantly higher mean MTBS (16.01 +/- 1.12 MPa) than did other groups (2.63 +/- 1.05 to 12.55 +/- 1.52 MPa) (p = 0.0001). In the groups where HF was not used, HTF (G3: 12.55 +/- 1.52 MPa) showed significantly higher MTBS than did HTA (G5: 2.63 +/- 1.05 MPa) (p < 0.05). All failure types were mixed, ie, adhesive between the resin cement and ceramic accompanied by cohesive failure in the cement.Conclusion: Heat treatment procedures for the pre-hydrolyzed silane either in a furnace or with the application of hot air cannot replace the use of HF gel for the adhesion of resin cement to feldspathic ceramic. Yet when mean bond strengths and incidence of pre-test failures are considered, furnace heat treatment delivered the second best results after the control group, being considerably better than hot air application.

Bismuth as a general internal standard for lead in atomic absorption spectrometry

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

Análise da viabilidade da utilização da cinza do bagaço de cana-de-açúcar como aglomerante para a produção de matrizes cimentantes

Pós-graduação em Engenharia Civil - FEIS

Strength of 3Y-TZP and feldspathic porcelain subjected to different cooling methods

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

Efeito de tratamentos térmicos nas propriedades mecânicas, eletroquímicas e citotoxidade de ligas do sistema Ti-15Mo-XNb

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