Estudo comparativo da queima rápida com a queima tradicional nas propriedades de materiais cerâmicos de base argilos

Dutra, R. P. S.; Varela,M. L.; Nascimento, R. M. ; Gomes, U. U. ; Martinelli1, A. E. ; Paskocimas, C. A. Estudo comparativo da queima rápida com a queima tradicional nas propriedades de materiais cerâmicos de base argilosa. Cerâmica [online]. 2009, vol.55, n.333, pp. 100-105. ISSN 0366-6913. doi:Disponivem em: . Acesso em: 04 out. 2010.

A Mismatch-Based Model for Memory Reconsolidation and Extinction in Attractor Networks

OSAN, R. , TORT, A. B. L. , AMARAL, O. B. . A mismatch-based model for memory reconsolidation and extinction in attractor networks. Plos One, v. 6, p. e23113, 2011.

Do talão de nota fiscal ao cupom fiscal: a implantação do ECF no estado do Rio Grande do Norte e sua repercussão na arrecadação do ICMS

The present paper has aimed the analysis of a real instrument which offers great impact in the ICMS revenue: The Fiscal Voucher Emitting Equipment (ECF). In this sense, the effects of the commercial automation process in Rio Grande do Norte s ICMS revenue between 2000 and 2006 were investigated. Based on this goal, the methodology adopted was characterized as a study of quantitative, exploratory-qualitative nature, through the collecting of secondary data, provided by the State Taxation Bureau (SET). In the absence of a statistic model in the existing literature about the approached theme, we decided for the elaboration of a suitable model, with tables and graphics. As a way to observe the effects of these programs on the revenue, the comparison between the ECF users and non users, in the same period, has proved to be of great importance. We reached the conclusion that even though the growth rates amongst the activities that use the ECF had ascended in tributary revenue in the related years, from 2004 on, with the introduction of TEF, this participation presented a higher growth, which leads us to suppose that the use of this recent instrument provides a significant impact in the State effective revenue. We stand out that the collected amounts could have been even higher, if the level of adhesion to the instrument had not been so low, mainly amongst the minor entrepreneurs, which may mean a rooted defraudation in the system. In short, through the set of data obtained, it is possible to conclude that the ECF and the recent TEF have significantly influenced the ICMS revenue in the entire State all over the period that was analyzed

É ensinando que se aprende: um estudo sobre o ensino de projeto no Curso de Arquitetura e Urbanismo da Universidade Federal do Rio Grande do Norte (CAU UFRN)

You cannot teach architectonic design, but only learn it. This sentence was, during some decades, especially during the modernism, the starting point, adopted by several architectonic design professors, when they had to approach their subject. An attitude that, some years ago, was reviewed and fighted by area s experts. This paper join this criticism, and try to add something to the pre-existing discussion, analyzing with the case-study method all the subjects related with architectonic design of the Architecture and Urbanism degree, at Universidade Federal do Rio Grande do Norte CAU/UFRN . The aim is to identify and analyze the teaching methodologies used by the professors and their effects related to the students. To reach this purpose four different methods were used: i) Professors interviews; ii) Different forms submitted to students and professors; iii) Daily practice s observation, developed during classes; iv) Documents analysis about the degree (historical development and subjects) and about the subjects themselves (summaries, table of contents and planning). Studying the results, it was possible to underline that, in spite of the efforts of some of the professors to find a way to teach with more appropriate educational and pedagogic bases, some of the teaching methodologies, criticized in articles dealing with the matter, were still used. With regard to these, the research pointed out some suggestions that could help to improve the teaching and learning process, joining professors and students that are the most important subjects of the teaching activity. Developing the idea living in the paper s title Teaching and learning , it s now clear that only the practice, through the improvement of the pedagogic techniques, together with critical analysis can help the professors to reach a relationship level, regarding the teaching and learning process, as that described in the epigraph s text, into which teaching and learning, can t be done only by one of the process subject, but must be lived by both of them: professors and students

O entre do carvão ao corpo - em - arte de ator-brincante

I propose with this paper a reflection on the experiences contained in the creation of the body- in-art (FERRACINI, 2006a, b) that originated the show Rosmaninhos... This process was developed within the coletivo UZUME teatro from João Pessoa PB, through recreations and resignifications of the corporeity and physicality contained in the steps, loas, aboios, songs and choreography observed in the manners that Mestre Zequinha plays in his group of Cavalo Marinho (Sea Horse), resident in the city of Bayeux - PB, and starting from the appropriation of the text Hamlet of William Shakespeare. The body-in-art is understood in this work as a vectorial body that dilates its daily functionality, recognizing a potential learning area capable to generate creative escape lines that destabilize the "subject centered in an individuality and identity" (FOUCAULT apud FERRACINI, 2006b, p.14), being open to the differentiation of itself, indicating the possible existence of an itself-other and of the exchange-in-art space. This process of construction of the body-in-art based on Master Zequinha s ways of playing the Cavalo Marinho was methodically guided by the appropriation of the coletivo UZUME teatro of the stages of Observation, Codification and Theatricalization contained in the technique of corporal mimeses proposed by the LUME Teatro (Campinas - SP). That use resulted in two phases: Active Observation and Composition of the body-in-art. Through the repetition of these aesthetic matrixes of the Cavalo Marinho, the actors discovered actions that when, codified and organized, can configure their body-in-art, which created a vectorial exchange-in-art space to what was found in the Cavalo Marinho party. This search proposed the means of potentiating the actors' work when it comes to a preparation that allowed to dilate the scenic presence and stimulated the production of actions, which culminated in the mounting of the show Rosmaninhos...

Análise de propriedades térmicas e mecânicas de compósitos de argamassa e resíduo de borracha

Although already to exist alternative technique and economically viable for destination of used tires, quantitative data on properties of constructive elements that use the rubber waste as aggregate still are restricted. In the present work, the waste proceeding from industry of retreading as material for manufacture of composite destined to the production of constructive elements was considered. Mechanical and thermal properties of mortar had been analyzed Portland cement with addition of waste without treatment, in the ratios of 10%, 20% and 30% in mass in relation to the mass of the cement, substituting the aggregate in the trace in mortar 1:5 mass cement and sand. The size of the used residue varied between 0,30mm and 4,8mm (passing in the bolter 4,8mm and being restrained in the one of 0,30mm), being it in the formats fibers and granular. The influences of the size and the percentage of residue added to the mortar (in substitution to the aggregate) in the thermal and mechanical properties had been considered. Assays of body-of-test in thestates had been become fullfilled cool (consistency index) and hardened (absorption of water for capillarity, strength the compression, traction and strength flexural). The work is centralized in the problem of the relation thermal performance /strength mechanics of used constructive systems in regions of low latitudes (Been of the Piauí), characterized for raised indices of solar radiation.

Efeito da velocidade de aquecimento nas propriedades de produtos da cerâmica estrutural

Heating rate is one of the main variables that determine a fire cycle. In industrial processes that use high temperatures, greater fire great can reduce the cost of production and increase productivity. The use of faster and more efficient fire cycles has been little investigated by the structural ceramic industry in Brazil. However, one of the possibilities that aims at modernizing the sector is the use of roller kilns and the inclusion of natural gas as fuel. Thus, the purpose of this study is to investigate the effect of heating rate on the technological properties of structural ceramic products. Clay raw materials from the main ceramic industries in the state of Rio Grande do Norte were characterized. Some of the raw materials characterized were formulated to obtain the best physical and mechanical properties. Next, raw materials and formulations were selected to study the influence of heating rate on the final properties of the ceramic materials. The samples were shaped by pressing and extrusion and submitted to rates of 1 °C/min, 10 °C/min and 20 °C/min, with final temperatures of 850 °C, 950 °C and 1050 °C. Discontinuous cycles with rates of 10 °C/min or 15 °C/min up to 600 °C and a rate of 20 °C/min up to final temperature were also investigated. Technological properties were determined for all the samples and microstructural analysis was carried out under a number of fire conditions. Results indicate that faster and more efficient fire cycles than those currently in practice could be used, limiting only some clay doughs to certain fire conditions. The best results were obtained for the samples submitted to slow cycles up to 600 °C and fast fire sinterization up to 950 °C. This paper presents for the first time the use of a fast fire rate for raw materials and clay formulations and seeks to determine ideal dough and processing conditions for using shorter fire times, thus enabling the use of roller kilns and natural gas in structural ceramic industries

Estudo paramétrico da injeção de vapor em reservatórios delgados

Exploration of heavy oil reservoirs is increasing every year in worldwide, because the discovery of light oil reservoirs is becoming increasingly rare. This fact has stimulated the research with the purpose of becoming viable, technically and economically, the exploration of such oil reserves. In Brazil, in special in the Northeast region, there is a large amount of heavy oil reservoir, where the recovery by the so called secondary methods Water injection or gas injection is inefficient or even impracticable in some reservoirs with high viscosity oils (heavy oils). In this scenario, steam injection appears as an interesting alternative for recover of these kinds of oil reservoirs. Its main mechanism consists of oil viscosity reduction through steam injection, increasing reservoir temperature. This work presents a parametric simulation study of some operational and reservoir variables that had influence on oil recovery in thin reservoirs typically found in Brazilian Northeast Basins, that use the steam injection as improved oil recovery method. To carry out simulations, it was used the commercial software STARS (Steam, Thermal, and Advanced Processes Reservoir Simulator) from CMG (Computer Modeling Group) version 2007.11. Reservoirs variables studied were horizontal permeability, vertical and horizontal permeability ratio, water zone and pay zone thickness ratio, pay zone thickness and thermal conductivity of the rock. Whereas, operational parameters studied were distance between wells and steam injection rate. Results showed that reservoir variables that had more influence on oil recovery were horizontal permeability and water zone and pay zone thickness ratio. In relation to operational variables, results showed that short distances between wells and low steam injection rates improved oil recovery

Avaliação dos efeitos de um extrato bruto de cianobactérias contendo microcistinas sobre o desempenho reprodutivo e a embriofetotoxicidade de ratos

The presence of cyanobacterial blooms in reservoirs intended for supply to the population can create public health problems for many species could produce potentially toxic compounds and these are not eliminated in the conventional procedures used in water treatment plants. So even in amounts less than the maximum allowable limit imposed by MS, cyanotoxins can be present in drinking water distributed to the population, creating a chronic exposure. There is little information about the long-term effects of oral exposure to cyanotoxins. This work aimed to show the exposure orally (v.o) of animals to a crude extract of cyanobacteria containing cyanotoxins to evaluate the reproductive performance of pregnant rats and their offspring and fertility of male rats. The presence of microcystins (MCs) in samples collected during the flowering processes in freshwater reservoirs in the Rio Grande do Norte, was analyzed by enzyme immunoassay and its variants have been identified and quantified by chromatographic methods. It was observed that by administration v.o. cyanobacterial extract containing MCs (40, 100 or 250 ng of MCs / kg / day) did not cause systemic toxicity in adult rats or effect on reproductive performance of male and female rats treated. It was also not observed any changes in skeletal study in the offspring of pregnant rats treated with the extract above. Because the solutions used contained MCs in a concentration equal to or greater than the tolerable daily intake for MCs, the results suggest, therefore, that the development of this work contributed to better assess public health risk as the oral exposure to cyanotoxins, increasing thus the credibility of the maximum allowable limit (LMP) of MCs in drinking water distributed to the population of several countries that use the LMP established by WHO in its legislation