Global well-posedness for the nonlinear wave equation in analytic Gevrey spaces

We obtain an asymptotic rate of decay for the radius of spatial analyticity of solutions to the nonlinear wave equation with initial data in the analytic Gevrey spaces

Sistemas Agroflorestais para a Mesorregião Sudoeste de Mato Grosso do Sul: um estudo propositivo.

bitstream/item/66228/1/31298.pdfOrganizado por: Alberto Feiden, Milton Parron Padovan, Adalgiza Inês Campolim, Aurélio Vinícius Borsato, Ivo de Sá Motta, João Batista Catto, Tércio Jacques Fehlauer

Descolagem de um revestimento cerâmico em fachada

A capacidade de um revestimento cerâmico resistir à descolagem depende da correcta selecção do produto de colagem e do método de colagem. Estes devem ser adequados à intensidade das acções previstas, ao tipo de utilização do revestimento, às características do suporte e ao tipo de revestimento. Uma cuidada concepção do revestimento e a selecção do produto de colagem adequado para cada situação não garante por si só a eficiência da colagem sendo necessário que essas precauções sejam acompanhadas de uma correcta execução. Nesta comunicação apresenta-se um trabalho onde se procedeu à análise das causas da des-colagem de um revestimento cerâmico de uma fachada. Procede-se à caracterização da situação existente e à descrição dos ensaios realizados. Propõem-se soluções de reabilitação e elaboram-se recomendações de aplicação

Estudo de um edifício de habitação multifamiliar com anomalias não estruturais

Os erros de construção grosseiros, a reduzida qualidade de execução, o deficiente acompanhamento/fiscalização dos trabalhos em obra, o completo desrespeito da legislação em vigor desde a fase de projecto não são invulgares. Estas situações provocam elevados prejuízos materiais, reduzem a qualidade de vida das populações e chegam por vezes a constituir risco para a vida. Nesta comunicação, apresenta-se um trabalho onde se procedeu ao levantamento das patologias de um edifício de habitação com alguns dos vícios anteriormente referidos. Realizaram-se várias visitas ao local, procedeu-se ao registo das anomalias, analisou-se o projecto de licenciamento e recolheu-se o testemunho de moradores. Fez-se uma análise das causas das patologias encontradas e propõem-se medidas correctivas

Development and characterization of an environmentallyfriendly process sequence (autohydrolysis and organosolv) for wheat straw delignification

The present work describes the delignification of wheat straw through an environmentally friendly process resulting from sequential application of autohydrolysis and organosolv processes. Wheat straw autohydrolysis was performed at 180°C during 30 min with a liquid–solid ratio of 10 (v/w); under these conditions, a solubilization of 44% of the original xylan, with 78% of sugars as xylooligosaccharides of the sum of sugars solubilized in the autohydrolysis liquors generated by the hemicellulose fraction hydrolysis. The corresponding solid fraction enrichment with 63.7% of glucan and 7.55% of residual xylan was treated with a 40% ethanol and 0.1% NaOH aqueous solution at a liquid–solid ratio of 10 (v/w), with the best results obtained at 180°C during 20 min. The highest lignin recovery, measured by acid precipitation of the extracted lignin, was 3.25 g/100 ml. The lignin obtained by precipitation was characterized by FTIR, and the crystallinity indexes from the native cellulose, the cellulose recovered after autohydrolysis, and the cellulose obtained after applying the organosolv process were obtained by X-ray diffraction, returning values of 21.32%, 55.17%, and 53.59%, respectively. Visualization of the fibers was done for all the processing steps using scanning electron microscopy.The authors thank Professor Juan Carlos Parajo from University of Vigo, for the assistance in the materials preparation under autohydrolysis process as well as the ALBAN program for the PhD fellowship support

Simple implementation of complex functionals: scaled selfconsistency

We explore and compare three approximate schemes allowing simple implementation of complex density functionals by making use of selfconsistent implementation of simpler functionals: (i) post-LDA evaluation of complex functionals at the LDA densities (or those of other simple functionals); (ii) application of a global scaling factor to the potential of the simple functional; and (iii) application of a local scaling factor to that potential. Option (i) is a common choice in density-functional calculations. Option (ii) was recently proposed by Cafiero and Gonzalez. We here put their proposal on a more rigorous basis, by deriving it, and explaining why it works, directly from the theorems of density-functional theory. Option (iii) is proposed here for the first time. We provide detailed comparisons of the three approaches among each other and with fully selfconsistent implementations for Hartree, local-density, generalized-gradient, self-interaction corrected, and meta-generalized-gradient approximations, for atoms, ions, quantum wells and model Hamiltonians. Scaled approaches turn out to be, on average, better than post-approaches, and unlike these also provide corrections to eigenvalues and orbitals. Scaled selfconsistency thus opens the possibility of efficient and reliable implementation of density functionals of hitherto unprecedented complexity.Comment: 12 pages, 1 figur

Continuous beer fermentation with yeast immobilized on alternative cheap carriers and sensorial evaluation of the final product

Continuous beer fermentation offers a wide range of advantages, mostly of economic nature over the traditional batch process. However, due to increased complexity of operation comparing to batch process, flavor problems, risk of contamination, yeast viability, carrier price and inconvenience of immobilization, the continuous beer fermentation has found few practical applications so far. The carrier cost represents a significant part of the investment costs and therefore the need for a cheap support material easy to regenerate is still relevant. This work deals with a complete continuous fermentation system for beer fermentation and maturation consisting of an airlift and a packed-bed reactor containing brewing yeast immobilized on spent grains and corncobs, respectively. The objective of this study was to verify the long-term performance of the system and the suitability of these new cellulose-based carrier materials made from brewing and agricultural by-products. Further the influence of feed rate and aeration rate on bioreactors fermentation performance, immobilized biomass load, ethanol production and flavor profile of both green and maturated beer was followed. The influence of process parameters on sensorial quality of beer has been studied by physicochemical methods as well as by sensorial analysis (acceptance and description tests) carried out by both consumers and experienced tasters. This work clearly demonstrated the technological feasibility of the continuous brewing based on yeast immobilization on cheap alternative carriers (spent grains, corncobs) for continuous production of a beer with a balanced flavor profile.Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BPD / 3541 / 2000.Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP) - Proc. 00/12767-4.Unicer SA.

Influence of different pre-treatment methods on the immobilization of brewer’s yeast on corn cob particles

Fundação para a Ciência e Tecnologia (FCT

High gravity batch and continuous processes for beer production: evaluation of fermentation performance and beer quality

This study deals with two innovative brewing processes, high gravity batch and complete continuous beer fermentation systems. The results show a significant influence of the variables such as concentration and temperature on the yield factor of the substrate into ethanol and consequently on the productivity of the high gravity batch process. The technological feasibility of continuous production of beer based on yeast immobilization on cheap alternative carriers was also demonstrated. The influence of process parameters on fermentation performance and quality of the obtained beers was studied by sensorial analysis. No significant difference in the degree of acceptance between the obtained products and some traditional market brands was found.FAPESP; CAPES; CNPq (Brazil); Malteria do Vale, Wallerstein Industrial e Commercial, Corn Products Brasil; Johnson-Diversey; FCT/Portugal; MŠMT Czech Republic; Unicer S.A