Avaliação da potencialidade de argilas do Rio Grande do Norte – Brasil

DUTRA, Ricardo Peixoto Suassuna ; SILVA, Jaquelígia Brito da ; MORAES, Márcio Luiz Varela Nogueira de ; NASCIMENTO, R. M. ; GOMES, Uilame Umbelino ; PASKOCIMAS, Carlos Alberto . Avaliação da potencialidade de argilas do Rio Grande do Norte. Cerâmica Industrial, v. 13, p. 47-50, 2008.

Influência do lodo de ETE na massa para fabricação de cerâmica vermelha

The WTP produce many kinds of residue on your treatment stages, but the sludge is the more problematic from the final disposition point view. The actual rate of residue production deriving from technological evolution and the crescent population needs prevents the subtle equilibrium generation between consumption and recycling/reuse, creating problems of pollution resulting from inappropriate management of residues. Thus, is necessary achieve a new equilibrium between the grow from raw materials and energy and the residue generation. This equilibrium should be achieved by technical and economic feasibility of environmental supported models through recycling and reuse. The red ceramic industry stand out in residue absorption question as raw material due their clay mass heterogeneity, constituted by clay minerals and non-clay minerals with wide mineralogical variation, allowing residue inclusion which act like plastic or non-plastic materials, contributing to retain heavy metals contained in residues in the vitreous mass formed during the burning of the ceramic bodies. This work propose the study of the influence of incorporation of 25 wt.% sludge from wastewater treatment plant, according preliminary results, in the mass to produce ceramic bodies. The raw materials was characterized through chemical composition analyses by XRF, mineralogical analyses by XRD, thermal analyses by TG and DTA, Atterberg limits and thermodilatometry. Subsequently was composed the mass with 75 wt.% of clay and 25 wt.% of dried wastewater sludge from UFRN WWTP. Samples with 6,0 x 2,0 x 0,5 cm was produced with unidirectional compacting under pressure of 20MPa and burned in temperatures between 950 and 1,200ºC. After fired, the ceramic bodies have been submitted to physical and mechanical analyses through the measure of firing shrinkage, water absorption, density, apparent porosity and flexural strength; crystallographic analyses through XRD and microstructure analyses by SEM. The technological properties obtained was satisfactory to production of roof tiles with 25 wt.% at 1,200 ºC, but the production of others products at lower temperatures was not feasible

Estudo de massa cerâmica triaxial visando à otimização do ciclo de queima da indústria de cerâmica estrutural

Over recent years the structural ceramics industry in Brazil has found a very favorable market for growth. However, difficulties related to productivity and product quality are partially inhibiting this possible growth. An alternative for trying to solve these problems and, thus, provide the pottery industry the feasibility of full development, is the substitution of firewood used in the burning process by natural gas. In order to contribute to this process of technological innovation, this paper studies the effect of co-use of ceramic phyllite and kaolin waste on the properties of a clay matrix, verifying the possible benefits that these raw materials can give to the final product, as well as the possibility of such materials to reduce the heat load necessary to obtain products with equal or superior quality. The study was divided into two steps: characterization of materials and study of formulations. Two clays, a phyllite and a residue of kaolin were characterized by the following techniques: laser granulometry, plasticity index by Atterberg limits, X-ray fluorescence, X-ray diffraction, mineralogical composition by Rietveld, thermogravimetric and differential thermal analysis. To study the formulations, specifically for evaluation of technological properties of the parts, was performed an experimental model that combined planning involving a mixture of three components (standard mass x phyllite x kaolin waste) and a 23 factorial design with central point associated with thermal processing parameters. The experiment was performed with restricted strip-plot randomization. In total, 13 compositional points were investigated within the following constraints: phyllite ≤ 20% by weight, kaolin waste ≤ 40% by weight, and standard mass ≥ 60% by weight. The thermal parameters were used at the following levels: 750 and 950 °C to the firing temperature, 5 and 15 °C/min at the heating rate, 15 and 45min to the baseline. The results showed that the introduction of phyllite and/or kaolin waste in ceramic body produced a number of benefits in properties of the final product, such as: decreased absorption of water, apparent porosity and linear retraction at burn; besides the increase in apparent specific mass and mechanical properties of parts. The best results were obtained in the compositional points where the sum of the levels of kaolin waste and phyllite was maximal (40% by weight), as well as conditions which were used in firing temperatures of 950 °C. Regarding the prospect of savings in heat energy required to form the desired microstructure, the phyllite and the residue of kaolin, for having small particle sizes and constitutions mineralogical phases with the presence of fluxes, contributed to the optimization of the firing cycle.

Avaliação da incorporação combinada dos resíduos de cascalho de perfuração de poço de petróleo e de polimento do porcelanato em cerâmica vermelha

Among the industries, those that produce ceramic porcelain for use in construction industry and oil, during the exploration and production period, play an important role in the production of waste. Much research has been carried out both by academia and the productive sector, sometimes reintroducing them in the same production line that generated them, sometimes in areas unrelated to their generation, as in the production of concrete and mortar for the construction, for example, but each one in an isolated way. In this research, the aim is to study the combined incorporation of the waste drill cuttings of oil well and the residue of the polishing of porcelain, generated in the final stage of finishing of this product in a clay matrix, for the production of red pottery, specifically bricks, ceramic blocks and tiles. The clay comes from the municipality of São Gonçalo, RN, the drilling waste is from the Natal basin, in Rio Grande do Norte, and the residue of the polishing proceeds from a ceramic porcelain of the State of Paraíba. For this purpose, we used a mixture of a plastic clay with a non-plastic, in a ratio of 50% each, settling formulations with the addition of these two residues in this clay matrix. In the formulations, both residues were incorporated with a minimum percentage of 2.5% and maximum of 12.5%, varying from 2.5% each, in each formulation, which the sum of the waste be no more than 15%. It should be noted that the residue of the polishing of ceramic porcelain is a IIa class (not inert). The materials were characterized by XRF, XRD, TG, DTA, laser granulometry and the plasticity index. The technological properties of water absorption, apparent porosity, linear shrinkage of burning, flexural tensile strength and bulk density were evaluated after the sintering of the pieces to 850 °C, 950 °C and 1050 °C, with a burning time of 3 hr, 3 hr and 30 minutes, and 3 hr and 50 minutes, respectively, with a heating rate of 10 °C/minute, for all formulations and landing of 30 minutes. To better understand the influence of each residue and temperature on the evaluated properties, we used the factorial planning and its surfaces of response for the interpretation of the results. It was found that the temperature has no statistical significance at a 95% of reliability level in flexural tensile strength and that it decreases the water absorption and the porosity, but increases the shrinkage and the bulk density. The results showed the feasibility of the desired incorporation, but adjusting the temperature to each product and formulation, and that the temperatures of 850 °C and 950 °C were the one that responded to the largest number of formulations

A encruzilhada da vida política em assentamentos de reforma agrária no Rio Grande do Norte

The rural settlements represent a mark in the expensive historical process of fight by the land in Brazil. At first offer basic terms of survival, through the access the land and of the fundamental supports for exploration. At the same time, have stimulated organization forms politicizes of the families who manage to work with the new challenges of the everyday. The moment that follows the land conquest, and therefore, the settlements construction while life and work project, it is crossed for objective and subjective demands, with highlight for options of agricultural production and strategies of collective action. Originally formed as representation instance legitimates of the families - front to the government and social actors - the settlers associations are private spaces for political sociability, that guided by principles participative, can lead the settlers the new conquests through indeed democratic experiences. The goal of this work is to comprehend the participation forms in the scope of these associations and the way as that translates in life best terms for the group, from the settlements experiences located in the Territories of the Citizenship Mato Grande and Açu-Mossoró, in Rio Grande do Norte's State. The theoretical conceptions that guide this analysis are concentrate on discussions about democracy and participation (Patermam, Putnam, Bodernave) and in the reflections about the rural world (Medeiros, Martins, Woodman e Woodman and Bergamansco). About methodological, different point of view strategies were developed: The direct observation, the application in locate of questionnaires to the families settlers and interviews semi-structured with the internal leaderships. With that could verify that the participation forms in the associations operate in two heartfelt: Of a side, they promote assimilation opportunities of democratic abilities accompanied of notions of social rights and redefinition of political standards; Of another, it offers indeed the possibility of the settlers lead, with relative autonomy, the political organization and her changes in direction to a way of life that wish to have in the settling

Estado e sociedade civil no Acre (1970-1980)

The relation between State and civil society is not a very recent discussion, but it does not mean that debate is exhausted, since is in the historical context that the novelty is seized. Thinking like this, we may analyze how the relation between state and civil society happened in Acre during the decade of 1970. But, to understand how this relation is established in faraway Acre, we have available to the reader historical analyses, in a tireless attempt to clarify minimally aspects that characterize acreana society. To do this, we take on as a departure point, in general not differentiating of the given structure at national level, the conformation of this society was guided in a passive revolution, in another way, by high transformismo, relegating to the civil society, which is incipient, pífia a simple participation in the hegemonic policy direction. All this brings us to the thought that both state bureaucracy structure and the civil society organization, were influenced decisively for a traditional political elite. In addition, we begin the work with the lifting bibliographic reference searching and then we analyze the empirical reality, such as newspapers, official media publications and private, a few documents and last, interviews with political actors associated with the process consolidation of civil society in the 1970 decade. The interviewees were selected, firstly for their location in the region, and for their outstanding contribution to the consolidating process of recent Acre history. Thus, the interviews followed up on a semi-structured way, leading up, also, for the informations that the interviewees would have to pass on. The systematization and analysis of these surveys have shown us that, in the period before of the Acre Federal State lifting had, of course, a transformismo by high, but at 1970decade, the society with a more heterogeneous social formation, is not allowed, or at least, organize itself, to counter a systematic imposition. Thus, the hegemonic area of dispute between State and civil society occurs from the "reconciliation" with the adoption of public policies that amenizasse the dispute between both spheres, and to build up some bodies, settling a acreana civil society.

Responsabilidade social empresarial: percepções e práticas do empresariado salineiro do Rio Grande do Norte.

The debate around the thematic of Corporate Social Responsibility - CSR involves economic, social, cultural and symbolic aspects in the relations established between company and society. In Brazilian reality, the CSR, understood as enterprise actions, external and/or internal, that contributes to social and ambient improvement, gains greater visibility in 1990 decade. Although the significant increase of theoretical productions about CSR pertinent elements, it is still scarce the studies that treats about the relation company/society in the northeastern reality, and singularly, in Rio Grande do Norte. It was in this perspective, that, in being the salt industry one of most important in the potiguar economic history formation , the present work investigated practicies and perceptions of salt entrepreneurship about CSR. Considering all the Rio Grande do Norte salt industry history phases, since the period of the Brazil s settling, as well as the characteristics of the study object, was opted to the qualitative research, objectified in interviews half-structuralized realized with the salt segment entrepreneurs, as well as professionals of ambient management and human resources working in potiguar salt segment. The research main results indicated a coexistence between the mechanisms of management seated on personal and paternalists relations, typical of traditional salt industry, and the emergency of innovative elements typical of the modern management, like the CSR. In this context, a tension between continuity and rupture with the traditional mechanisms of management in salt entrepreneurship actions

Utilização intracoágulo de espuma fibrinolítica - preparação, caracterização e atividade in vitro de uma espuma de estreptoquinase e proposta de uma nova abordagem terapêutica

Foam was developed as a novel vehicle for streptokinase with the purpose of increasing the contact time and area between the fibrinolytic and the target thrombus, which would lead to a greater therapeutic efficacy at lower doses, decreasing the drug s potential to cause bleeding. Fibrinolytic foams were prepared using CO2 and human albumin (at different v:v ratios), as the gas and liquid phases, respectively, and streptokinase at a low total dose (100,000 IU) was used as fibrinolytic agent conveyed in 1 mL of foam and in isotonic saline solution. The foams were characterized as foam stability and apparent viscosity. The thrombolytic effect of the streptokinase foam was determined in vitro as thrombus lysis and the results were compared to those of a fibrinolytic solution (prepared using the same dose of streptokinase) and foam without the fibrinolytic. In vitro tests were conducted using fresh clots were weighed and placed in test tubes kept at 37 ° C. All the samples were injected intrathrombus using a multiperforated catheter. The results showed that both foam stability and apparent viscosity increased with the increase in the CO2:albumin solution ratio and therefore, the ratio of 3:1 was used for the incorporation of streptokinase. The results of thrombus lysis showed that the streptokinase foam presented the highest thrombolytic activity (44.78 ± 9.97%) when compared to those of the streptokinase solution (32.07 ± 3.41%) and the foam without the drug (19.2 ± 7.19%). We conclude that fibrinolytic foam showed statistically significant results regarding the enhancement of the lytic activity of streptokinase compared to the effect of the prepared saline solution, thus it can be a promising alternative in the treatment of thrombosis. However, in vivo studies are needed in order to corroborate the results obtained in vitro

Educação e sustentabilidae :Assentamento Maria da Paz - João Câmara/RN

This work is a research and action in the field of enviromental education, oriented for the construction of the land s distribuction of the Maria da Paz Settling, in João Câmara/RN, as process of social learning, collecive production of new knowledge, values and attitudes related to the environment. It was consolidated through a partnership beteween the UFRN (GERAH/DARQ and GEPEM/DEPED), MST and INCRA/RN. The drawing that represents the way the space organization of the settling was made constructed through effort of many people, in a process of dicussion with the community had as technical support the environment inventory (soil, vegetation, water resources, and others) allowing the agro-ecology zoning of the settlers participation conditions, their contradiction and conflicts, the challenges that appear in the search for consensus and the factor that creat chages