Artigos Científicos - ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3360

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Gerenciamento dos resíduos sólidos dos serviços de saúde: aspectos do manejo interno no município de Marituba, Pará, Brasil
(2009-12) SALES, Carla Cristina de Lima; SPOLTI, Gracieli Pâmela; LOPES, Maria do Socorro Bezerra; LOPES, David Franco
Medical wastes offer a potential risk to public health and the environment before an inadequate management. This study aims to verify aspects of internal handling of medical wastes in the city of Marituba, Pará State. By means of questionnaires and field visits, a descriptive and observational study was performed in 13 health establishments in the city. The total volume of generated medical wastes was about 13,000kg/week. There were deficiencies in many stages of the internal handling, for example the internal treatment that was performed in only one of the establishments, external storage made in 4 establishments and in precarious ways, among many others. Also, there were conformities as packing in adequate bags and containers as well as common waste separation. In general way, the federal norms were not accomplished and management of medical wastes in health establishments needs adequacy in every stage of the handling in order to control and reduce risks, decreasing the quantity of residues.
Acesso aberto (Open Access)
Fatty acid profiles and tocopherol contents of buriti (Mauritia flexuosa), patawa (Oenocarpus bataua), tucuma (Astrocaryum vulgare), mari (Poraqueiba paraensis) and inaja (Maximiliana maripa) fruits
(2010) RODRIGUES, Antonio Manoel da Cruz; DARNET, Sylvain Henri; SILVA, Luiza Helena Meller da
Amazonian fruits are rich in fat but have a fatty acid profile that may be beneficial in relation to risk of coronary heart disease. Amazonian fruits also contain other potentially cardioprotective constituents including tocopherols. Tocopherol profiles were determined by high performance liquid chromatography (HPLC), and fatty acid profiles were determined by gas chromatography (GC). In the present study, the total oil content, fatty acid composition and tocopherol content of the pulps of five Amazonian fruits (buriti, patawa, tucuma, mari and inaja) were measured. The total oil content of the fruits ranged from 31.0 to 41.8%. The major fatty acid in all of the fruits was oleic acid (C18:1), though substantial levels of palmitic acid (C16:0) were present. Linoleic acid (C18:2) was the main polyunsatured fatty acid observed. α-Tocopherol was the most prevalent tocopherol except in buriti pulp. Buriti and mari pulp have a high content in α-tocopherols with 297 and 155 µg g-1 of dry matter. Our data indicate that all five of these Amazonian fruits are good sources of unsaturated fatty acids and tocopherols.
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Quantificação de cianeto total nas etapas de processamento das farinhas de mandioca dos grupos seca e d'água
(Instituto Nacional de Pesquisas da Amazônia, 2010-03) CHISTÉ, Renan Campos; COHEN, Kelly de Oliveira; MATHIAS, Erla de Assunção; OLIVEIRA, Suzy Sarzi
The aim of this work was to quantify the total cyanide concentration during the production stages of cassava flour from dry and water groups. In relation to dry flour, the total cyanide concentration in the cassava root reduced from 160±11.8 mg HCN/kg to 149±12.3 mg HCN/kg after grinding, 68±2.5mg HCN/kg after pressing and 5±0.2 mg HCN/kg was obtained in the final product after the roasting process. For the water flour production, the cassava root showed 321±21.6 mg HCN/kg total cyanide content, and during the fermentation process, the total cyanide content for the first 24-hour fermentation was from 297±2.7 mg HCN/kg reaching 64±2.3 mg HCN/kg after resting in a pool for 96 hours. After grinding and pressing the fermented roots, the values lowered to 50±0.6 and 36±0.4 mg HCN/kg, respectively. A concentration of 9±0.1 mg HCN/kg was obtained in the final product, evidencing the detoxification process efficiency in both processings.
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Análise estatística do comportamento mecânico à compressão do compósito cimento-madeira
(2011) MACÊDO, Alcebíades Negrão; LIMA, Alexandre Martins de; FONSECA, Fábio de Oliveira; LAVÔR, Bárbara Valéria de Abreu
The present work has the objective to propose the use of saw dust wood waste from the tropical wood industry mainly located at Belém, Pará State, for the fabrication of wood-cement composites. Due to the natural chemical incompatibility between wood and cement, this procedure results in a set retarding effect, with wood specie depending intensity. This by-effect can be overcome by using procedures such as additives, wood mineralization, accelerated carbonation and others. Analysis were made based on axial compression strength data with samples aged 28 days for mortars made with 2, 3.5 and 5% wood content in mass, using cements type CP I and CP II, with and without Calcium Clorets-based set accelerator additive. The data there from obtained was statistically analyzed to evaluate the influence of the wood content and of additives on the mechanical strength. Most of the research works developed so far make use of reforestation waste, very little being available about tropical wood waste. So, this work represents a pioneer effort in developing a cement-bonded wood composite with regionally available materials and residues from Belém, Pará State.
Acesso aberto (Open Access)
FBG optimization using spline encoded evolution strategy
(2011-06) SOUSA, Marco José de; COSTA, João Crisóstomo Weyl Albuquerque; SOUZA, Remo Magalhães de; PANTOJA, Ramon Villar Monte Palma
This paper presents an encoding scheme adapted for Fiber Bragg Grating (FBG) optimization using metaheuristics. The proposed encoding scheme uses spline approximations in order to build softened refractive index profiles from few encoded parameters. This approach is suitable for Fiber Bragg Grating (FBG) synthesis because it ensures both the reduction of the problem dimensionality and the respect of important restrictions associated to the FBG manufacture. Simulations are shown where an ES using the spline encoding was able to converge faster and produce more interesting filters, when compared with conventional encoding schemes.
Acesso aberto (Open Access)
Estabilizador de sistemas de potência digital aplicado a uma unidade geradora da UHE de Tucuruí
(2011-10) NOGUEIRA, Fabrício Gonzalez; BARRA JUNIOR, Walter; COSTA JÚNIOR, Carlos Tavares da; BARREIROS, José Augusto Lima; NASCIMENTO FILHO, Paulo Sergio; MORAES, Anderson Roberto Barbosa de; GOMES, Marcus Ciro Martins; LANA, Jânio José de
This paper presents the development and results of field tests of a digital power system stabilizer (PSS), designed for the damping of electromechanical oscillations in interconnected systems. Experimental tests were performed in a 350 MVA hydrogenerator unit, of the Tucurui Power Plant. The PSS damper control law was embedded in a digital hardware system based on a digital signal controller (DSPIC 30f5011). The structure of the control law is in discrete time RST canonical form, and the controller parameters were calculated using the pole shifting technique. For purposes of the controller design, the dynamics of the plant, in the considered operating point, was represented by a parametric model, which was estimated from data measured in the field. The experimental results showed an excellent performance of the damping of electromechanical modes observable UHE Tucurui by digital PSS.
Acesso aberto (Open Access)
An automatic methodology for obtaining optimum shape factors for the radial point interpolation method
(2011-12) MACHADO, Péricles Lopes; OLIVEIRA, Rodrigo Melo e Silva de; SOUZA, Washington César Braga de; ARAÚJO, Ramon Cristian Fernandes; TOSTES, Maria Emília de Lima; GONÇALVES, Cláudio
In this letter, a methodology is proposed for automatically (and locally) obtaining the shape factor c for the Gaussian basis functions, for each support domain, in order to increase numerical precision and mainly to avoid matrix inversion impossibilities. The concept of calibration function is introduced, which is used for obtaining c. The methodology developed was applied for a 2-D numerical experiment, which results are compared to analytical solution. This comparison revels that the results associated to the developed methodology are very close to the analytical solution for the entire bandwidth of the excitation pulse. The proposed methodology is called in this work Local Shape Factor Calibration Method (LSFCM).
Acesso aberto (Open Access)
Processamento e caracterização de snack extrudado a partir de farinhas de quirera de arroz e de bandinha de feijão
(2012-03) CARVALHO, Ana Vânia; BASSINELLO, Priscila Zaczuk; MATTIETTO, Rafaella de Andrade; CARVALHO, Rosângela Nunes; RIOS, Alessandro de Oliveira; SECCADIO, Lara Lima
The objective of this work was to develop a new formulation for a snack made by thermoplastic extrusion from a mixture of broken rice flour and broken common bean flour, and assess the nutritional, sensory and technological potential of the new product. The broken common bean flour was added to the broken rice flour at a rate of 30%, and the snack was produced in a pilot scale single screw extruder. The extrusion parameters were fixed using three extrusion zones (at 40, 60 and 85 °C); screw speed of 177 rpm; feed rate of 292 g.min-1; and a circular matrix with a diameter of 3.85 mm. The snack sample was submitted to physicochemical, technological and sensory analyses. A significant effect of adding the broken common bean flour was observed in increasing the levels of protein and fiber in the snack, when compared with only broken rice flour. With respect to the technological characteristics, a bulk density of 0.17 g.cm-3 was obtained, expansion rate of 7.75 and instrumental hardness of 435.98 g.f. The formulation was well accepted, with an acceptance rate of 76% for overall impression. It was concluded that it was possible to produce extruded snacks by incorporating 30% of broken common bean flour into broken rice flour, resulting in gluten free products with good sensory acceptance and adequate nutritional value.
Acesso aberto (Open Access)
Zeólita A sintetizada a partir de rejeitos do processo de beneficiamento de caulim
(2012-06) SANTANA, Daniela Lira de; SARAIVA, Augusto Cesar Fonseca; NEVES, Roberto de Freitas; SILVA, Denilson Luz da
Raw materials were used to synthesize zeolite A as an alternative and more economical source of silica and aluminum, using waste from the kaolin of the paper industry. Zeolites are crystalline substances with a structure characterized by a framework of linked tetrahedra, each one consisting of four oxygen atoms surrounding a cation. The development of processes for the synthesis of zeolites is of great interest for use in the areas of purification, adsorption and catalysis.The starting materials for the synthesis of zeolite A consisted of wastes from kaolin beneficiation of paper companies of Pará state, Brazil.The zeolite was obtained after calcination at 85 and 110 ºC during 24 h.The chracterization of the starting material was performed by X-ray diffraction, chemical analysis, thermogravimetric and differential thermal analysis, and scanning electron microscopy.The characterization of zeolite A was done by X-ray diffraction and scanning electron microscopy. The kaolin waste used as starting material showed to be essentially kaolinite mineral. For the temperatures and time used in the synthesis it was possible to form the crystalline phase of zeolite A for the two starting materials.
Acesso aberto (Open Access)
Reaproveitamento de cinzas de carvão mineral na formulação de argamassas
(2012-06) SIQUEIRA, Jacilene Siqueira de; SOUZA, Célio Augusto Gomes de; SOUZA, José Antônio da Silva
This paper aims to study the ash incorporation from the combustion of coal in fluidized bed boilers, in production of mortar, replacing part of cement. Specimens were prepared using Portland cement to the specifications CPII-E-32 of normal characteristics and classification of sand below 100 mesh. Blends in the 4:1 ratio, that is, 4 parts of aggregate to 1 part of cement, with insertion of ashes in the proportions 0, 10, 20, 30, 40 and 50%. The mortar was developed in mixing and casting was made in a mold of 5 cm x 10 cm. The behavior of compressive strength was evaluated after 28 days; the strength decreases with increasing percentage of ash. Additional analysis was carried out by X-ray diffraction, and it was found that the substitution of this waste can be successfully used in mortars with blends of up to 30%.
Acesso aberto (Open Access)
Processing and characterization of extruded breakfast meal formulated with broken rice and bean flour
(2012-09) CARVALHO, Ana Vânia; MATTIETTO, Rafaella de Andrade; BASSINELLO, Priscila Zaczuk; KOAKUZU, Selma Nakamoto; RIOS, Alessandro de Oliveira; MACIEL, Renan de Almeida; CARVALHO, Rosângela Nunes
The objective of this work was to develop an extruded breakfast product containing broken rice and split old beans and to verify the influence of the extrusion process on their physicochemical, technological, and sensory characteristic. The final product had a protein content of 9.9 g.100 g-1, and therefore it can be considered a good source of proteins for children and teenagers. The dietary fiber content of the final edible product was 3.71 g.100 g-1. Therefore, the breakfast meal may be considered as a source of dietary fiber according to Brazilian law . As for the technological properties, the extruded product presented an expansion index of 8.89 and apparent density of 0.25 g.cm-3. With regard to the sensory analysis, the acceptance average was ranked between 6.8 and 7.7, corresponding to the categories "liked slightly" and "liked very much". With regard to purchase intention, 79% of the panelists said they would certainly or possibly purchase the product. Broken rice and split old beans are interesting alternatives for the elaboration of extruded breakfast products presenting good nutritional, technological, and sensory qualities.
Acesso aberto (Open Access)
Regionalização de curvas de permanência de vazão de regiões hidrográficas do estado do Pará
(2012-12) COSTA, Andréia Silva; CARIELLO, Brunna Lucena; BLANCO, Claudio José Cavalcante; PESSOA, Francisco Carlos Lira
This paper describes the regionalization of flow duration curves for rivers located in the Calha Norte and Xingu hydrologic regions, in the Brazilian state of Pará. Recorded data at 25 stream gauge stations located in the regions were used for model fitting. The flow duration curves were calibrated by using of 5 regression models (power, exponential, logarithmic, quadratic, and cubic). The cubic model was found to be the best-fit to the flow duration curves of the Calha Norte. The exponential model was found to be the best-fit to the flow duration curves of the Xingu. The spatial variation of each model parameter was studied in order to explain its corresponding variation in terms of the drainage area, mean annual precipitation, river length and slope. The models were validated to estimating the flow duration curves at two chosen watersheds of each region, with good agreement of the simulated and observed plotting flows. In mathematical words, the good fitting was represented by the relative mean square error and the Nash-Sutcliffe coefficient calculated for the cubic model (Calha Norte) and for the exponential model (Xingu) . The good performance of the models suggests that they can be used to simulate the flow duration curves for the considered regions.
Acesso aberto (Open Access)
Green-Markov models - new optimization strategies: a case study for user allocation in co-channel macro/femto networks
(2012-12) CARDOSO, Diego Lisboa; SANTANA, Ádamo Lima de; SILVA, Marcelino Silva da; FRANCÊS, Carlos Renato Lisboa; COSTA, João Crisóstomo Weyl Albuquerque; CARVALHO, Solon Venâncio de; VIJAYKUMAR, Nandamudi Lankalapalli
The femtocell concept aims to combine fixed-line broadband access with mobile telephony using the deployment of low-cost, low-power third and fourth generation base stations in the subscribers' homes. While the self-configuration of femtocells is a plus, it can limit the quality of service (QoS) for the users and reduce the efficiency of the network, based on outdated allocation parameters such as signal power level. To this end, this paper presents a proposal for optimized allocation of users on a co-channel macro-femto network, that enable self-configuration and public access, aiming to maximize the quality of service of applications and using more efficiently the available energy, seeking the concept of Green networking. Thus, when the user needs to connect to make a voice or a data call, the mobile phone has to decide which network to connect, using the information of number of connections, the QoS parameters (packet loss and throughput) and the signal power level of each network. For this purpose, the system is modeled as a Markov Decision Process, which is formulated to obtain an optimal policy that can be applied on the mobile phone. The policy created is flexible, allowing different analyzes, and adaptive to the specific characteristics defined by the telephone company. The results show that compared to traditional QoS approaches, the policy proposed here can improve energy efficiency by up to 10%.
Acesso aberto (Open Access)
Comportamento reológico de suco misto elaborado com frutas tropicais
(2013-06) BEZERRA, Carolina Vieira; SILVA, Luiza Helena Meller da; COSTA, Rebeca Desireé Sousa da; MATTIETTO, Rafaella de Andrade; RODRIGUES, Antonio Manoel da Cruz
The rheological properties of a juice blend obtained from a tropical fruit mix were determined in this work using a rotational viscosimeter at temperatures from 10 ºC to 60 ºC. The Power law and Mizrahi-Berk models were fitted to the experimental data. All the models were considered adequate to describe the rheological properties of the juice blend according to the fitted statistical parameters. The behaviour index of the product was below 1.0, indicating the pseudoplasticity of the juice. The behaviour indexes for consistency were found to decrease with increase in temperature. The effect of temperature on the rheological behaviour of the juice was described by an Arrhenius type equation and discussed in terms of the activation energy (Ea). The values for Ea varied from 4.27 to 4.66 kcal.gmol-1 with increases in shear rate.
Acesso aberto (Open Access)
Caracterização completa da madeira da espécie amazônica Paricá (Schizolobium amazonicum Herb) em peças de dimensões estruturais
(2013-12) ALMEIDA, Diego Henrique de; SCALIANTE, Ricardo de Mello; MACEDO, Laurenn Borges de; MACÊDO, Alcebíades Negrão; DIAS, Antonio Alves; CHRISTOFORO, André Luis; CALIL JUNIOR, Carlito
The Amazon specie Paricá (Schizolobium amazonicum Herb) present fasts growth and very good development in diameter in a few years, a small amount of nodes and defects, key characteristic in its use for structural purpose. The aim of this paper was to determine the strength and stiffness properties of Paricá wood, according to ABNT NBR 7190: 2011, as well, perform the visual classification of members for determination of defects as: nodes, inclination of grain, warpings. The concluding that the Paricá wood is classified as C 20 dicotyledonous class, low density, with good compression strength parallel to the grain, with a great potential to be used in civil construction, when compared with other species and, in relation to the visual analysis, few nodes, right grain and has no warping.
Acesso aberto (Open Access)
Análise do potencial pozolânico da cinza de casca de arroz (CCA) através da técnica de refinamento de Rietveld
(2014-06) CORDEIRO, Luciana de Nazaré Pinheiro; MASUERO, Ângela Borges; DAL MOLIN, Denise Carpena Coitinho
Rice husk ash (RHA) is an agricultural by-product with well-known pozzolanic properties. However, the widespread commercial use of RHA is hindered by the lack of consistency between batches of this material and by the lack of quick and inexpensive quality control parameters. This study presents some basic principles for the quantification of the amorphous phases of RHA with the assumption that mineralogic characterization with X-ray diffraction can be a good quality control method for use residual or controlled ashes. The samples in this study were prepared with a lithium fluoride (LiF) standard and phase quantification was carried out using Rietveld's refinement method. The analysis of the phases was successfully conducted and results were satisfactory, with maximum relative standard deviation of 5%. These results show that quantitative analysis by Rietveld refinement can be used in the characterization of construction waste.
Acesso aberto (Open Access)
Wavelength assignment using a hybrid evolutionary computation to reduce cross-phase modulation
(2014-06) MIRANDA, André Moacir Lage; LIMA, Fabio de Oliveira; ROCHA, Helder Roberto de Oliveira; VIJAYKUMAR, Nandamudi Lankalapalli; FRANCÊS, Carlos Renato Lisboa; SEGATTO, Marcelo Eduardo Vieira; COSTA, João Crisóstomo Weyl Albuquerque
In this paper, we propose a hybrid methodology based on Graph-Coloring and Genetic Algorithm (GA) to solve the Wavelength Assignment (WA) problem in optical networks, impaired by physical layer effects. Our proposal was developed for a static scenario where the physical topology and traffic matrix are known a priori. First, we used fixed shortest-path routing to attend demand requests over the physical topology and the graph-coloring algorithm to minimize the number of necessary wavelengths. Then, we applied the genetic algorithm to solve WA. The GA finds the wavelength activation order on the wavelengths grid with the aim of reducing the Cross-Phase Modulation (XPM) effect; the variance due to the XPM was used as a function of fitness to evaluate the feasibility of the selected WA solution. Its performance is compared with the First-Fit algorithm in two different scenarios, and has shown a reduction in blocking probability up to 37.14% when considered both XPM and residual dispersion effects and up to 71.42% when only considered XPM effect. Moreover, it was possible to reduce by 57.14% the number of wavelengths.
Acesso aberto (Open Access)
Identificação de patologias em fachadas e metodologia de análise: estudos de casos na Universidade Federal do Pará
(Universidade Federal do Pará, 2014-10) CARVALHO, Isabella Chaves; PICANÇO, Marcelo de Souza; MACÊDO, Alcebíades Negrão
The system of external cladding of the building acts as a protective layer and contributes to the proper aspect. The facade is subject to the action of agents of degradation as one of the most exposed areas of the building, with the presence of pathology becoming responsible for high repair costs. Research suggests as a goal, a survey on of buildings facades in the Federal University of Pará, to acquire grants to run future interventions in public facilities from the identification of the main problems present in the case studies. Started the development of evaluation methods to identify the damage with a standardized manner from the document production that facilitate visual inspections with obtaining information from damage. From the result of the identification of pathologies in facades with their respective methods of analysis, was expected to contribute to the increase in procedures that seek technical and economic performance of façades as a whole, assisting in future maintenance of the buildings in question, as well as production of reference source for other ventures.
Acesso aberto (Open Access)
Efeito de aditivos no comportamento reológico do rejeito da bauxita
(Universidade Federal do Pará, 2015-03) GONÇALVES, Silvane Gonçalves e; BRUM, Sebastião Martins; FELIPE, Augusta Maria Paulain Ferreira; SOUZA, José Antônio da Silva; FERREIRA, Keylla Castro
In the bauxite mining in Parogominas, PA, Brazil, tailings are discarded in the processing with 33.5% of solids content and small particle size with D50 below 5 µm. These factors contribute to this suspension basically formed by silicoaluminates, with high concentrations of kaolinite clay, increase the viscosity and the yield stress, these factors are important during the pumping. It was performed granulometric analysis and determined the chemical and mineralogical composition of the material. It was studied the use of the sodium hexametaphosphate and polyacrylamide 25% anionic to decrease the viscosity. The result show that the viscosity decrease with use of 23.8 g/ton for the polyacrylamide and 101.75 g/ton for the sodium hexametaphosphate. The particle size and the pH have influence in the behavior of the additives.
Acesso aberto (Open Access)
Santa Casa de Misericórdia e as políticas higienistas em Belém do Pará no final do século XIX
(2015-04) MIRANDA, Cybelle Salvador; BELTRÃO, Jane Felipe; HENRIQUE, Márcio Couto; BESSA, Brena Tavares
The article analyzes the relationship between hygienist policies in effect in Belém in the late nineteenth century and the expansion of activities of the Santa Casa de Misericórdia do Pará. Considered one of the first hospital institutions in the former Grão-Pará Province, in addition to its own hospital, the Brotherhood administered several other health facilities in the capital, and the study of its physical displacement made it possible to “map” three health centers in Belém: Pioneer, Expansion and the Santa Casa, which reinforce the growth vectors of the city. The expansion of its activities is configured as the expansion of the Santa Casa de Misericórdia to serve the underprivileged and sick, preceding the establishment of a public health system in Pará.