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Search Results: 1 - 10 of 19318 matches for " Gilberto Ant?nio Tavares "
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The Use of Solid State NMR to Evaluate the Carbohydrates in Commercial Coffee Granules  [PDF]
Regina Freitas Nogueira, Elisangela Fabiana Boffo, Maria Inês Bruno Tavares, Leonardo A. Moreira, Leila Aley Tavares, Antnio Gilberto Ferreira
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.24050
Abstract: Coffee brings many health benefits due to its chemical constituents. Based on this information, it is essential to know the main chemical compounds from coffee granules; the intermolecular interaction among the coffees compounds and the molecular components homogeneity. In this study six types of roasted commercial coffee were evaluated by solid state nuclear magnetic resonance (NMR), employing carbon-13 (13C) and hydrogen (1H) nucleus. Carbon-13 was analyzed applying high field NMR techniques, such as: magic angle spinning (MAS); magic angle spinning with cross-polariza- tion (CPMAS) and magic angle spinning with cross-polarization and dipolar dephasing (CPMASDD). The hydrogen was evaluated via relaxation times. Proton spin-lattice relaxation time in the rotating frame was deter-mined through the carbon-13 decay, during the variable contact-time experiment, using high field NMR. Proton spin-lattice relaxation time was determined through the inversion-recovery pulse sequence, using low field NMR. Considering all NMR results, it was concluded that the major coffee compounds are: a) triacilglycerides, which constitute the mobile region in the granule coffee and b) Carbohydrates such as: polysaccharides and fibers that belong to the rigid domain. These constituents belong to different molecular mobility domain, although they have strong intermolecular interactions due to the granule organization.
ABRA ADEIRA DE NáILON: RESISTêNCIA à TRA O EM TESTES FíSICOS E SEU EMPREGO COMO CERCLAGEM NO FêMUR DE C ES
Afonso Henrique Miranda,Luiz Antnio Franco da Silva,Gilberto Antnio Tavares,Andréia Vitor Couto do Amaral
Ciência Animal Brasileira , 2006,
Abstract: A abra adeira é uma fita de náilon 6.6 (poliamida -PA) e tem sido empregada, após esteriliza o, em vários procedimentos cirúrgicos, dentre os quais a redu o de fraturas de ossos longos. Neste estudo, primeiramente, avaliou-se a resistência à tra o dessas abra adeiras mediante testes de esfor o físico específicos, realizados em seu estado natural e autoclavado. Posteriormente, foi realizada uma avalia o qualitativa da resistência empregando-se a abra adeira na redu o ou na imobiliza o de fratura oblíqua de fêmur em c es, para verifica o da resistência do material a tra o e a seguran a de seu sistema de trava após sua aplica o. O dispositivo mostrou-se resistente à autoclavagem, aos testes de esfor o físico e à aplica o no foco de fratura. Concluiu-se que a abra adeira de náilon é resistente à tra o tanto em seu estado natural como após a autoclavagem e pode ser uma op o na fixa o de fraturas oblíquas de fêmur. PALAVRAS-CHAVES: C es, cerclagem, fêmur, fratura, náilon, poliamida.
CARACTERíSTICAS FíSICAS E MICROBIOLóGICAS DO CENTRO TENDíNEO DIAFRAGMáTICO BOVINO CONSERVADO EM GLICERINA A 98% E NO GLUTARALDEíDO A 4%
Rogério Elias Rabelo,Gilberto Antnio Tavares,Neusa Margarida Paulo,Luiz Antnio Franco da Silva
Ciência Animal Brasileira , 2006,
Abstract: Realizaram-se testes físicos de tra o e alongamento até ruptura em dez tiras com 5 a 6 mm de largura, do exemplar in natura e dos respectivos exemplares conservados em glicerina a 98% e glutaraldeído a 4% por 30 dias para a avalia o da influência de ambos os conservantes sobre o tecido biológico, com vistas ao aproveitamento em cirurgias reparadoras. Paralelamente, avaliou-se a atividade anti-séptica dos conservantes, por meio de exames microbiológicos de fragmentos colhidos do material in natura e dos respectivos exemplares submetidos à conserva o. Os testes físicos mostraram que sete amostras conservadas em glutaraldeído a 4% suportaram maior for a de tens o, quando comparadas com os respectivos exemplares in natura e conservados em glicerina a 98%. Duas amostras apresentaram comportamento semelhante quanto ao ponto de rompimento, para ambos os conservantes. Apenas em uma amostra verificou-se que o material in natura apresentou um ponto de rompimento superior às amostras conservadas. Observou-se crescimento bacteriano apenas em quatro amostras no material in natura. Os mesmos exames realizados em amostras conservadas n o revelaram nenhum crescimento. Conclui-se que tanto a glicerina a 98%quanto o glutaraldeído a 4% demonstraram ser eficientes na conserva o do material, bem como na atividade bactericida durante o período de 30 dias.
Distribui??o sedimentar da Lagoa Rodrigo de Freitas através de sísmica de alta resolu??o
Baptista Neto, José Antnio;Silva, Cleverson Guizan;Dias, Gilberto Tavares de Macedo;Fonseca, Estefan Monteiro da;
Revista Brasileira de Geofísica , 2011, DOI: 10.1590/S0102-261X2011000100013
Abstract: the rodrigo de freitas lagoon (rio de janeiro state) sediments and bottom characteristics were analyzed using high-resolution (10 khz) sub-bottom profiles associated with particle size analyses of 44 bottom sediment samples. four types of echo-characters were identified revealing the strong relation with the particle size distribution and bottom morphology. in areas of acoustic penetration, the basement delineates buried sugar-loaf hills and infilled-valley features. the total sediment thickness can reach as much as 16 meters along the paleovalleys, which are aligned in a ne-sw direction, parallel to the regional basement orientation observed on the coastal massifs. there is a predominance of organic rich muddy sediments, infilling the paleovalleys which are the main sites of shallow gas occurrences within the lagoonal sediments.
Spectroscopic Analysis of a Theropod Dinosaur (Reptilia, Archosauria) from the Ipubi Formation, Araripe Basin, Northeastern Brazil
Jo?o Hermínio da Silva,Francisco Eduardo de Sousa Filho,Antnio álamo Feitosa Saraiva,Nádia Amanda Andrade,Bartolomeu Cruz Viana,Juliana Manso Say?o,Bruno Tavares de Oliveira Abagaro,Paulo de Tarso Cavalcante Freire,Gilberto Dantas Saraiva
Journal of Spectroscopy , 2013, DOI: 10.1155/2013/437439
Abstract: The Araripe Sedimentary Basin is known by the excellence of its fossils, regarding the preservation, diversity, and quantity. Here, we present a spectroscopic analysis using several experimental techniques (X-ray energy dispersion spectroscopy, Fourier-transform infrared spectroscopy) as well as X-ray diffraction and thermogravimetric analysis applied in small fragments of bones from the posterior members of a theropod dinosaur. The results agree regarding the different composition of the stone matrix and the fossilized bone, indicating a partial substitution of the material by elements present in the depositional environment. However, differently from what is believed to occur, there is evidence that pyritization is not the only mechanism of fossilization for a specimen of Ipubi formation, but calcification, additionally, plays an important role in the fossil production of this Formation. 1. Introduction The geological process of sedimentation, which has happened throughout millions of years, can include the preservation of animal and vegetal specimens from ancient times under the form of fossils [1]. The occurrence of this process involves a series of chemical events, many not yet completely understood. For the fossil preservation, for example, it is known that total or partial alteration of its chemical composition is verified. Some of the most important processes include the dissolution and removal of mineralized material by the interstitial waters which seep into the bone and replace the chemicals with rock-like minerals. The process of fossilization involves dissolving and replacing the originals minerals in the object (such as hydroxyapatite) with other minerals (such as calcite) [1]. In alkaline regions, the dissolution of the silicon dioxide is more probable to occur, while in regions highly acidic, the dissolution of the calcium carbonate it is supposed to happen. Diverse processes can be associated with different regions, but even in only one region it is possible to be associated with many mechanisms of fossilization [2, 3]. In the Brazilian depositional scenario the Araripe Sedimentary Basin is one of the localities where different fossilization processes act. Located among the states of Ceará, Pernambuco, and Piauí, at the northeast of Brazil, it comprises around 12,000?km2, and it is considered the largest interior northeastern sedimentary basin [4]. From a geological point of view, Araripe Basin is formed by four main stratigraphic sequences [4]: (i) a Paleozoic sequence composed of the Cariri formation; (ii) a Juro-Neocomian sequence
O problema do cociente partidário na teoria e na prática brasileiras do mandato representativo
Tavares, José Antnio Giusti;
Dados , 1999, DOI: 10.1590/S0011-52581999000100005
Abstract: the electoral system affects in advance and decisively the nature of representative mandates and the legitimacy of legislative decisions. majoritarian systems decrease the density of the representative mandate and, when districts are numerically small in terms of both representatives and constituency, such systems tend to curtail the independence of elected officeholders, whose actions can be monitored by the dominant local groups. on the other hand, proportional systems that operate with numerically large districts maximize the density of representative mandates and, at the same time, ensure the elected officeholder the independent responsibility that characterizes the modern representative mandate. there are, however, three varieties of proportional systems (flexible list, open list, and no list) where the vote cast for candidates from different parties or inter-party electoral coalitions eliminate the party quota and jeopardize party identity both inside and outside the legislative realm. in the brazilian case, this mechanism follows and reinforces the individualistic and atomistic tradition of the political elites
O problema do cociente partidário na teoria e na prática brasileiras do mandato representativo
Tavares José Antnio Giusti
Dados , 1999,
Abstract: The electoral system affects in advance and decisively the nature of representative mandates and the legitimacy of legislative decisions. Majoritarian systems decrease the density of the representative mandate and, when districts are numerically small in terms of both representatives and constituency, such systems tend to curtail the independence of elected officeholders, whose actions can be monitored by the dominant local groups. On the other hand, proportional systems that operate with numerically large districts maximize the density of representative mandates and, at the same time, ensure the elected officeholder the independent responsibility that characterizes the modern representative mandate. There are, however, three varieties of proportional systems (flexible list, open list, and no list) where the vote cast for candidates from different parties or inter-party electoral coalitions eliminate the party quota and jeopardize party identity both inside and outside the legislative realm. In the Brazilian case, this mechanism follows and reinforces the individualistic and atomistic tradition of the political elites
As diversas vidas de Zé Bebelo
Coelho Marco Antnio Tavares
Estudos Avan?ados , 2003,
Abstract:
The Evaluation of Polyethylene/Clay Composite from Solid State NMR  [PDF]
Regina F. Nogueira, Maria Inês B. Tavares, Rosane A. S. San Gil, Antnio G. Ferreira
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.25060
Abstract: Polymeric nanocomposites based on polyethylene (PE) and Brazilian natural montmorillonite clay (MN) were obtained by melt processing, using a twin-screw extruder. The main objective of this work is focusing on the characterization of composites materials by solid-state nuclear magnetic resonance (NMR). The solid-state NMR measurements were used to observe both polymer matrix (through carbon-13 and hydrogen nuclei) and the clay (silicon-29 and aluminum-27). The polymer matrix analyses were carried out applying solid state techniques, such as: cross-polarization magic angle spinning (CPMAS), variable contact time (VCT) and by the proton spin-lattice relaxation time in the rotating frame parameter (TH), detected from the resolved carbon-13 decay of the VCT experiment and through the determination of spin-lattice relaxation time, T1H (using low field NMR). The clay was analyzed by 29Si and 27Al, employing MAS NMR technique. From those techniques we can have principally response on clay dispersion in the polyethylene matrix, as well as the interactions between both components in the nanostructured material. The T1H response was an important result which showed, that the materials formed, presented different molecular domains (according to the domain size that varied from 25 to 50 nm, measured by relaxation), considering the clay dispersion mode in terms of intercalation and/or exfoliation in the polymer matrix.
Avalia o imobilária: Dois casos da importancia das vistas como externalidades Tasación de la propriedad: Dos casos sobre la importancia de las vistas de la propriedad como algo externo Real estate appraisal: two cases on the importance of the views as externalities
Fernando Tavares,António Moreira,Elizabeth Pereira
Revista Portuguesa e Brasileira de Gest?o , 2012,
Abstract: Este artigo faz parte de uma investiga o académica sobre a avalia o imobiliária em Portugal. O seu principal objetivo é o de avaliar as externalidades positivas geradas pelas vistas para o mar e pelo layout do empreendimento, de forma a saber quais s o as variáveis com maior impacto. A nível metodológico foram analisados dois empreendimentos: um em Espinho, vocacionado para o segmento residencial, e outro em Troia, vocacionado para o segmento de turismo/lazer. Constata-se que a externalidade mais relevante no empreendimento de Espinho é a variável vista para o mar , seguida da variável piso , verificando-se que, quanto mais elevado for o piso, maior o valor económico do imóvel. Quanto ao empreendimento em Troia, a variável que mais contribui para a externalidade positiva é a proximidade à marina . Ao contrário do empreendimento residencial, o rés-do-ch o é o piso mais importante no empreendimento de Troia. Este artículo es parte de una investigación académica sobre la tasaciones inmobiliaria en Portugal. Su objetivo principal es evaluar como externalidad el impacto positivo generado por las vistas al mar y la disposición del desarrollo inmobiliario, a fin de conocer cuáles son las variables con mayor impacto. Metodológicamente se analizaron dos proyectos: uno en Espinho, dise ado para el segmento residencial, y otro en Troia, ideal para el turismo/ocio. Parece que la externalidad más importante en el desarrollo de Espinho es la variable “vistas al mar”, seguido de la variable “piso”, comprobando que cuanto más alto este el piso, mayor es el valor económico de la propiedad. En cuanto al desarrollo en Troia, la variable que más contribuye a la externalidad positiva es la proximidad a la “marina”. A diferencia del desarrollo residencial, la planta baja es el piso más importante en Troia. This article is part of an academic research about real estate appraisal in Portugal. Its main objective is to evaluate, on one hand, positive externalities generated by the views to the ocean and by the project layout and, on the other hand, its impact on property values. Methodologically, two real estate properties were analyzed. One is located in Espinho, targeted to the residential market segment, and another in Troia, belonging to the tourism and leisure segment. In the Espinho property, the most influential positive externality with the largest contribution, is the variable “views to the ocean”, being followed by the variable “floor”. As regards the Troia Resort property, the variable that most contributes to positive externalities is the proximity to the “marin
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