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Search Results: 1 - 10 of 417356 matches for " M.; Costa "
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Effect of Waste Oil-Cracking Catalyst Incorporation on Durability of Mortars  [PDF]
Carla Costa, M. Sofia Ribeiro, Nuno Brito
Materials Sciences and Applications (MSA) , 2014, DOI: 10.4236/msa.2014.513092
Abstract: This paper presents research on transport properties and alkali-silica reaction (ASR) susceptibility of mortars containing a pozzolanic waste generated in the fluid catalytic cracking (wFCC) unit by the Portuguese oil-refinery. For this purpose, two series of mortars were prepared by partially replacing cement with 5%, 10% and 15% of wFCC catalyst. The main difference between the two series of mortars is the sand reactivity used in their composition. The results revealed that wFCC catalyst blended cement mortars exhibit an increased resistance against capillary water absorption and chloride migration, as well as a considerable inhibition effect on deleterious ASR expansion. However, under the adopted experimental conditions the incorporation of wFCC catalyst in mortars decreases their carbonation resistance.
The Use of Eucalyptus Activated Biocarbon for Water Treatment-Adsorption Processes  [PDF]
Roberta M. Nunes, Damaris Costa, Nilce Ortiz
American Journal of Analytical Chemistry (AJAC) , 2017, DOI: 10.4236/ajac.2017.88037
Abstract: A biocarbon after activation process showed the removal percentage of 92% of methylene blue in solution, the equilibrium parameter—RL value was in the interval from 0 to 1, with 46% of surface coverage degree. The Freundlich constant (n) was higher than 1 as an indication of the physical adsorption process. The Radlich-Peterson calculations obtained the higher R2 value which g constant near 1, a high similarity with Langmuir model. Temkin constant B1 was a positive indication of endothermic process. All calculations provided favorable results for the use of activated biocarbon for dye removing and possible for other organic substances.
Optical Triangulation-Based Microtopographic Inspection of?Surfaces
Manuel F. M. Costa
Sensors , 2012, DOI: 10.3390/s120404399
Abstract: The non-invasive inspection of surfaces is a major issue in a wide variety of industries and research laboratories. The vast and increasing range of surface types, tolerance requirements and measurement constraints demanded during the last decades represents a major research effort in the development of new methods, systems and metrological strategies. The discreet dimensional evaluation the rugometric characterization and the profilometric inspection seem to be insufficient in many instances. The full microtopographic inspection has became a common requirement. Among the different systems developed, optical methods have the most important role and among those triangulation-based ones have gained a major status thanks to their flexibility, reliability and robustness. In this communication we will provide a brief historical review on the development of optical triangulation application to the dimensional inspection of objects and surfaces and on the work done at the Microtopography Laboratory of the Physics Department of the University of Minho, Portugal, in the development of methods and systems of optical triangulation-based microtopographic inspection of surfaces.
Acta Biológica Colombiana , 2007,
Abstract: this paper deals with the conceptions, knowledge and attitudes of the inhabitants of the county of pedra branca, bahia state, on the arthropods of the class diplopoda. data were collected from february to june 2005 by means of openended interviews carried out with 28 individuals, which ages ranged from 13 to 86 years old. it was recorded some traditional knowledge regarding the following items: taxonomy, biology, habitat, ecology, seasonality, and behavior. results show that the diplopods are classified as “insects”. the characteristic of coiling the body was the most commented, as well as the fact that these animals are considered as “poisonous”. in general, the traditional zoological knowledge of pedra branca’s inhabitants concerning the diplopods is coherent with the academic knowledge.
A vontade segundo Jacotot e o desejo de cada um
Netto, M?nica Costa;
Educa??o & Sociedade , 2003, DOI: 10.1590/S0101-73302003000100018
Abstract: this paper describes the experience of working with jacques ranciere's the ignorant schoolmaster in a continuing education course for adult educators in the state of rio de janeiro during the second semester of 2002. the question of the will involved in the act of learning is discussed. it draws from course participants' reactions to the principles of emancipatory education as elaborated by joseph jacotot (france, 19th century), which are presented in ranciere's book.
Famílias e acesso diferenciado a escolas públicas prestigiadas: um estudo de caso
Costa, Márcio da;
Educa??o em Revista , 2010, DOI: 10.1590/S0102-46982010000200011
Abstract: the article brings up results from a piece of research carried out in six municipal schools holding opposed reputations. we accomplished structured observa tions, interviews and questionnaires in three very different areas of rio de janeiro. the demand for the schools and the perception of the educational bureaucracy were the cri teria for their school's selection. the research seeks to understand how the school pres tige arises and is sustained, considering that this prestige is a relevant factor for the dis tribution of educational opportunities and is strongly tied to social hierarchies and strat ification. we highlight hierarchies and social inequalities within social contexts that are usually thought of as homogenous: the "ordinary" public schools. the pertinent litera ture was reviewed with special attention to school choice and segmentation among and within schools. some results were selected stressing the strength of the family condition ing to help comprehending the phenomenon under our focus.
Cricket singing means rain: semiotic meaning of insects in the district of Pedra Branca, Bahia State, northeastern Brazil
Costa Neto, Eraldo M.;
Anais da Academia Brasileira de Ciências , 2006, DOI: 10.1590/S0001-37652006000100007
Abstract: this paper deals with the semiotic meanings which are given both to the appearance and/or behavior of insect species according to the ethnoentomological knowledge of the inhabitants of the village of pedra branca, bahia state, brazil. data were collected from february to may 2001 by performing open-ended, recorded interviews with nine men and twenty-five women, whose ages ranged from 19 to 82 years old. data were analyzed by using the union model, which involves considering all available information on the surveyed subject. twelve kinds of insects were associated with both beneficial and harmful events, as well as with the indication of changing weather. the way local people perceive and interpret the appearance and/or behavior of certain species of insects depends on the cultural background of each inhabitant. the following semiotic meanings were recorded: fatal, funereal, auspicial, meteorological, societal, monetary, and of abundance or scarcity. the beliefs in the augural power of insects in the village of pedra branca are deep-rooted in the local tradition and are transmitted from generation to generation through oral culture. it is hoped that the data now available will be incorporated into a curriculum by those researchers interested in insect conservation and ethnobiology as well.
Rela??o entre grau de resistência a Hemileia Vastarix e produtividade no café Icatu
Costa, W. M.;
Bragantia , 1978, DOI: 10.1590/S0006-87051978000100001
Abstract: plants of the icatu coffee populations have been classified for resistance to h. vastatrix, using a six point scale, under field conditions. the relationship between total yield of three years and reaction types was studied. the variability in yield within each reaction type was also determined. it was observed that the average yield of selected plants, with a total production over 10 kg, does not differ significantly between reaction types. besides no significant differences were found between the four icatu population studied: h 4782-7, h 4782-10, h 4782-13, and h 3851-2. total yield of individual plants has been classified in classes of 2 kg, observing a range of 2 to 30 kg. it was observed that the most susceptible reaction types 5 and 6 are less frequent at the higher yield intervals, thus suggesting a reduction of top yields due to rust infection. the great variability in total plant yield observed in the icatu populations, indicates the possibility of selection for high yield within each of the six reaction types of resistance to h. vastatrix.
Violências e conflitos intersubjetivos no Brasil contemporaneo
Costa, Arthur Trindade M.;
Caderno CRH , 2011, DOI: 10.1590/S0103-49792011000200008
Abstract: in this paper, we discuss the interpersonal violence in brazil, which most visible consequence is the increase in homicide mortality. we suggest that the key to understanding this violent phenomenon is to understand the context in which these deaths occurred, ie, the type of conflict, its significance for the parties involved, its object and its structure. finally, we argue that, although dramatic, intersubjective violence has received little attention from the brazilian authorities.
Filosofia aberta, modelos de negócios e agências de fomento: elementos essenciais a uma discuss?o sobre o acesso aberto à informa??o científica
Costa, Sely M. S.;
Ciência da Informa??o , 2006, DOI: 10.1590/S0100-19652006000200005
Abstract: in order to stimulate the discussion about open access to scientific information, this paper examines an open philosophy, which is related to the use of tools, strategies, methodologies and policies that points out a new way of depicting the scholarly communication process - particularly in terms of publishing - while providing a basis for its interpretation, as well. this new model is based on a growing concern about the availability of knowledge to a greater number of people interested in it. such knowledge is created as a result of both scientific research (scientific knowledge) and the action of human beings on the society (cultural heritage). the text focuses solely on questions related to open access to scientific knowledge. in this regard, it deals with three issues: the major international initiatives on open access; new business models for scholarly and scientific journals as a response to these initiatives; the role performed by funding agencies in this context, aiming at the validation of these new models. it also introduces into the discussion the issue of disciplinary differences determined by communication patterns within scholarly communities concerning information production, dissemination and use. in conclusion, the paper presents a brief analysis of the impact that the open access movement produces upon the main scholarly communication actors, namely, universities and their researchers, scientific publishers and funding agencies.
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