Nitretação em plasma com gaiola catódica: investigação do mecanismo e estudo comparativo com a nitretação em plasma de tensão contínua

The ionic plasma nitriding is one of the most important plasma assisted treatment technique for surface modification, but it presents some inherent problems mainly in nitriding pieces with complex geometries. In the last four years has appeared a plasma nitriding technique, named ASPN (Active Screen Plasma Nitriding) in which the samples and the workload are surrounded by a metal screen on which the cathodic potential is applied. This new technique makes possible to obtain a perfect uniform nitrided layer apart from the shape of the samples. The present work is based on the development of a new nitriding plasma technique named CCPN (Cathodic Cage Plasma Nitriding) Patent PI 0603213-3 derived from ASPN, but utilizes the hollow cathode effect to increase the nitriding process efficiency. That technique has shown great improvement on the treatment of several types of steels under different process conditions, producing thicker and harder layers when compared with both, ASPN and ionic plasma nitriding, besides eliminating problems associated with the later technique. The best obtained results are due to the hollow cathode effect on the cage holes. Moreover, characteristic problems of ionic plasma nitriding are eliminated due to the fact that the luminescent discharge acts on the cage wall instead of on the samples surface, which remains under a floating potential. In this work the enhancement of the cathodic cage nitriding layers proprieties, under several conditions for some types of steels was investigated, besides the mechanism for nitrides deposition on glass substrate, concluding that the CCPN is both a diffusion and a deposition process at the same time

Obtenção de polímeros de LCC para aplicação como antioxidante de biodiesel de soja

Biodiesel is a fuel obtained from vegetable oils, such as soy, castorbean, among others. The monoester of fatty acid of these oils have chains with mono, di and tri double connections. The presence of these insaturations are susceptible to oxidization. Antioxidants are substances able to prevent oxidization from oils, fats, fat foods, as well as esters of Alquila( biodiesel). The objective of this work is to summarize a new antioxidant from the Cashew Nut Shell Liquid (CNSL) using the electrolysis technique. A current of 2 amperes was used in a single cell of only one group and two eletrodos of stainless steel 304 in a solution of methanol, together with the eletrolits: acetic acid, sodium chloride and sodium hydroxide, for two hours of agitation. The electrolysis products are characterized by the techniques of cromatography in a thin layer, spectroscopy of infrared and gravimetric analysis. The material was submitted to tests of oxidative stability made by the techniques of spectropy of impendancy and Rancimat (EN 14112). The analyses of characterization suggest that the polimerization of the electrolytic material ocurred. The application results of these materials as antioxidants of soy biodiesel showed that the order of the oxidative stability was obtained by both techniques used

Desenvolvimento de argamassa para restauração utilizando resíduo do polimento do porcelanato

The coatings mortars are essential elements of building structures because they execute an important role in protecting walls and are particularly exposed to aggressive action responsible for its degradation over time. The importance of wall coverings has been the subject of discussion and analysis in the conservation and rehabilitation of old buildings. Are sometimes removed and replaced with inappropriate solutions of constructive point of view or architecture. The most commonly used coatings on walls of old buildings is based on traditional hydraulic lime mortars. The present study aims at the formulation of new lime- based mortars and aerial fine aggregate, in order to contribute to a better field of conservation and restoration mortar coating of old buildings. Residue was used for polishing porcelain as fine aggregate, replacing the aggregate (sand), in percentages 05-30% by mass. We conducted a thorough evaluation of the mortar properties in fresh and hardened state by comparing the performance of the same with a reference mortar. The residue used was characterized as the density, bulk density, and particle size laser, scanning electron microscopy, X-ray diffraction and X-ray fluorescence. Formulations were produced 7, 6 with residue and one commonly used formulation, which served as a reference. In the formulations of lime mortars air (hydrated lime powder CH-I) has been adopted a stroke volume (1:3) with constant binder, was varied and the water / binder and aggregate and waste. For evaluation of mortars fresh, proceeded to consistency analysis, specific gravity, water retention and air content embedded. In the hardened state assays were performed in specific gravity, water retention, modulus of elasticity, tensile strength in bending, compressive strength, water absorption by capillary action, adhesion, tensile strength, resistance to shrinkage and salts by of crystallization trials with resources chloride solution, nitrate and sulfate all sodium in prismatic at 90 days of age, in addition to the micro structural analysis of mortars. Based on the results we can see that the mortar formulated with 10% content of waste and the reference free retraction feature more stable closer to neutrality. The composition of 10% was obtained better performance against the action of the salt crystallization. The mortar with 15% residue obtained better density, lower air content embedded and high capacity for water retention developing good workability. The replacement of 20% of waste generates a satisfactory utilization of resistance to compression, flexion and traction grip the base. And, finally, it can be seen that the mortar with 10, 15 and 20% residual show, in principle, good suitability as coatings, thus enabling a final result consistent with durability, workability and aesthetics developing therefore a material with better performance to repair or replace existing mortars in old buildings

Estudo sobre as potencialidades de compósitos à base de gesso e fibras de coco seco para aplicação na construção civil

The use of gypsum, one of the oldest building materials for the construction industry in the country has been experiencing a significant and steady growth, due to its low cost and some of its properties that confer comparative advantage over other binder materials. Its use comprises various applications including the coating of walls and the production of internal seals and linings. Moreover, the fibers are being increasingly incorporated into arrays fragile in an attempt to improve the properties of the composite by reducing the number of cracks, the opening of the same and its propagation velocity. Other properties, depending on the function of the component material or construction, among these thermal and acoustic performances, are of great importance in the context of buildings and could be improved, that is, having better performance with this embodiment. Conduct a comparative study of physico-mechanical, thermal and acoustic composite gypsum incorporating dry coconut fiber, in the form of blanket, constituted the main objective of this work. Improving the thermal and acoustic performances of precast gypsum, used for lining and internal vertical fences of buildings, was the purpose of development of these composites. To evaluate the effect of fiber content on the properties of the composites were used to manufacture the composite layer with different thicknesses. The composites were fabricated in the form of plates with dimensions of 500x500x24mm. To facilitate the comparative study of the properties were also made with material gypsum boards only. We then determined the physico-mechanical, thermal and acoustical plaster and composites. The results indicated that the composites were significant gains in relation to thermal performance and also acoustic, in certain frequency range, increasing the thickness of the blanket. Concerning other physical-mechanical properties, the results showed that although the compressive strength was lower than for the composite did not occur after a fracture catastrophic failure. The same trend was observed with regard to resistance to bending, since the composites have not suffered sudden rupture and still continued after the load supporting point of maximum load

Estudo do resíduo fosfogesso na formulação de uma pasta para revestimento interno de edifícios

Universidade Federal do Rio Grande do Norte

Implementação de um Módulo de Supervisão para um Sistema de Detecção de Vazamentos em Dutos de Petróleo

The transport of fluids through pipes is used in the oil industry, being the pipelines an important link in the logistics flow of fluids. However, the pipelines suffer deterioration in their walls caused by several factors which may cause loss of fluids to the environment, justifying the investment in techniques and methods of leak detection to minimize fluid loss and environmental damage. This work presents the development of a supervisory module in order to inform to the operator the leakage in the pipeline monitored in the shortest time possible, in order that the operator log procedure that entails the end of the leak. This module is a component of a system designed to detect leaks in oil pipelines using sonic technology, wavelets and neural networks. The plant used in the development and testing of the module presented here was the system of tanks of LAMP, and its LAN, as monitoring network. The proposal consists of, basically, two stages. Initially, assess the performance of the communication infrastructure of the supervisory module. Later, simulate leaks so that the DSP sends information to the supervisory performs the calculation of the location of leaks and indicate to which sensor the leak is closer, and using the system of tanks of LAMP, capture the pressure in the pipeline monitored by piezoresistive sensors, this information being processed by the DSP and sent to the supervisory to be presented to the user in real time

A rede de marcação e recaptura: o caso de borboletas do gênero heliconius

(The Mark and Recapture Network: a Heliconius case study). The current pace of habitat destruction, especially in tropical landscapes, has increased the need for understanding minimum patch requirements and patch distance as tools for conserving species in forest remnants. Mark recapture and tagging studies have been instrumental in providing parameters for functional models. Because of their popularity, ease of manipulation and well known biology, butterflies have become model in studies of spatial structure. Yet, most studies on butterflies movement have focused on temperate species that live in open habitats, in which forest patches are barrier to movement. This study aimed to view and review data from mark-recapture as a network in two species of butterfly (Heliconius erato and Heliconius melpomene). A work of marking and recapture of the species was carried out in an Atlantic forest reserve located about 20km from the city of Natal (RN). Mark recapture studies were conducted in 3 weekly visits during January-February and July-August in 2007 and 2008. Captures were more common in two sections of the dirt road, with minimal collection in the forest trail. The spatial spread of captures was similar in the two species. Yet, distances between recaptures seem to be greater for Heliconius erato than for Heliconius melpomene. In addition, the erato network is more disconnected, suggesting that this specie has shorter traveling patches. Moving on to the network, both species have similar number of links (N) and unweighed vertices (L). However, melpomene has a weighed network 50% more connections than erato. These network metrics suggest that erato has more compartmentalized network and restricted movement than melpomene. Thus, erato has a larger number of disconnected components, nC, in the network, and a smaller network diameter. The frequency distribution of network connectivity for both species was better explained by a Power-law than by a random, Poissom distribution, showing that the Power-law provides a better fit than the Poisson for both species. Moreover, the Powerlaw erato is much better adjusted than in melpomene, which should be linked to the small movements that erato makes in the network

Biologia alimentar e morfohistologia do tubo digestório do mussum, synbranchus marmoratus, bloch (osteichthyes: synbranchidae) no açude Marechal Dutra Gargalheiras , localizado no semi-árido brasileiro

Food habits and morpho-histology of the digestive tract of marbled swamp eel, Synbranchus marmoratus (Block, 1917) were investigated. The fish samples were captured during August, 2007 to July, 2008 in the Marechal Dutra reservoir, Acari, Rio Grande do Norte. The rain fall data was obtained from EMPARN. The fish captured, were measured, weighed, dissected, eviscerated and individual stomach weights were registered. The stomach contents analyses were carried out based on volumetric method, points, frequency of occurrence and applying the Index of Relative Importance. The degrees of repletion of the stomachs were determined besides the Index of Repletion relating to feeding activity variations and frequency of ingestion during the rainy and dry seasons. The rainfall varied from 0 mm a 335 mm with a mean value of 71.62 mm. Highest rainfall of 335.5 mm was registered in March, 2008 and August to December was the dry period. During the dry period the study species presented high degrees of repletion of the stomachs, with a peak value in the month of September (mean = 4.54; ± SD = 0.56). The minimum mean value of = 3.99 ± SD = 0.25 was registered in the month of May during the rainy period. The stomach contents of S. marmoratus registered show that this fish prefers animals, 78.22% of crustaceans 2.85% of mollusks, 3.25% of fish, 1.4% of insects and 13.5% of semi-digested organic matter, thus characterizing the study species as a carnivore with a preference for crustaceans. The morpho-histological aspects of the digestive tract of S. marmoratus indicate that the mouth is terminal adapted to open widely, thin lips with taste buds, small villiform teeth forming a single series on maxillas, four pairs of branchial arches with short and widely spaced branchial rays. The oesophagus is short and cylindrical with a small diameter. The oesophagus wall is thick with mucas surface and internal parallel folds. The stomach is retilinical in form, presenting cardiac, caecal and pyloric portions. The caecal portion is long and is intermediary in position between the cardiac and pyloric portions. The cardiac portion of the stomach is short and cylindrical formed of simple epithelial cylindrical mucus cells. The caecal portion is long with narrow walls, a big cavity and smaller folds which give rise to gastric glands. The phyloric portion has no glands and primary or secondary mucas folds. The morphohistological aspects of the digestive tract of S. marmoratus indicate its adaptation to a carnivorous feeding habit

Avaliação de parâmetros de estresse oxidativo em plantas de cana-de-açúcar tratadas com peróxico de hidrogênio

The genus Saccharum belongs to Poaceae family. Sugarcane has become important monocultures in Brazil due to their products: ethanol and sugar. The production may change between different regions from Brazil. This difference is related to soil, climatic conditions and temperature that promotes oxidative stress that may induce an early flowering. The aim of this work was to identify the effects of oxidative stress. In order to analyse this, sugarcane plants were submitted to oxidative stress using hydrogen peroxide. After this treatment, the oxidative stress were analyzed Then, the plant responses were analyzed under different approaches, using morphophysiological, biochemical and molecular tools. Thus, sugarcane plants were grown under controlled conditions and until two months they were subjected first to a hydroponics condition for 24 hours in order to acclimation. After this period, these plants were submitted to oxidative stresse using 0 mM, 10 mM, 20 mM and 30 mM hydrogen peroxide during 8 hours. The histomorphometric analysis allowed us to verify that both root and leaf tissues had a structural changes as it was observed by the increased in cell volume, lignin accumulation in cell walls. Besides, this observation suggested that there was a change in redox balance. Also, it was analyzed the activity of the SOD, CAT and APX enzymes. It was observed an increase in the SOD activity in roots and it was also observed a lipid peroxidation in leaves and roots. Then, in order to identify proteins that were differently expressed in this conditions it was used the proteomic tool either by bidimensional gel or by direct sequencing using the Q-TOF EZI. The results obtained with this approach identified more than 3.000 proteins with the score ranging from 100-5000 ions. Some of the proteins identified were: light Harvesting; oxygenevolving; Thioredoxin; Ftsh-like protein Pftf precusor; Luminal-binding protein; 2 cys peroxiredoxin e Lipoxygenase. All these proteins are involved in oxidative stress response, photsynthetic pathways, and some were classified hypothetical proteins and/or unknown (30% of total). Thus, our data allows us to propose that this treatment induced an oxidative stress and the plant in response changed its physiological process, it made changes in tissue, changed the redox response in order to survival to this new condition

Situações de Risco, Trabalho e Saúde de Imigrantes Brasileiros: representações sociais

This study searches in approaching diverse pertinent aspects to the immigration process that affects the countries of the European Union especially in Portugal. The works deriving from this research has its objective in: analyzing the risk, work and health in Brazilian immigrants residing in Lisbon, Portugal. As methodological way, we use the instruments: Test of Free Association of Words and half-structuralized interview. For in such a way, they had been processed in software s for analysis between them: SPSS 14,5, Evoc, Trideux and Alceste. The not-boarded results in this study will be worked as clippings and will be sent for posterior publication. Thus, I consider this work enriching, in view of contributing of the same as mechanisms of understanding of being a immigrant and the possibility of the mobilization of the society and the academic environment for a phenomenon growing each time more, especially, the professionals of health, so we can intervine in a more necessary form within the factors that affects this population layer directly

Relação entre ambiente familiar e capacidade funcional de idosos residentes no município de Jequié-BA

(Objective) Assess the functional capacity and determine the difference between the means of functional capacity (basic and instrumental activities of daily living) and the age groups of elderly residents in an outlying area in the hinterland of Bahia/Northeast of Brazil. (Methods) Analytical study with cross-sectional design and a sample of 150 elderly individuals enrolled in four Health Units in the municipality of Jequié, Bahia, Brazil. The instrument consisted of sociodemographic and health data, the Barthel Index and the Lawton scale. (Results) In all, 78.00% of the elderly were classified as dependent in the basic activities and 65.33% in the instrumental activities of daily living. Using the Kruskal- Wallis test, we found a statistically significant difference between the means of instrumental activities and the age groups (p= 0.011). (Conclusion) An elevated number of elderly were classified as dependent in terms of functional capacity and increased age is related to greater impairment in the execution of instrumental activities of daily living

Significados e percepções do homem diante da gravidez de sua companheira com síndromes hipertensivas

The general aim of the research was to comprehend the Social Representations constructed by the man in the face of his companion s risk pregnancy caused by hypertensive syndromes. The study is of exploratory and descriptive character in a qualitative approach developed at two public maternity hospitals, both located in Natal-RN, with 65 men whose wives had undergone high-risk pregnancy. The project was submitted to the Ethics on Research Committee of the Federal University of Rio Grande do Norte, Brazil (CEP-UFRN), with favorable report no. 81/07. For data collection, the following multimethods were employed: a word free association test; a projective test for registering mental images; and a semistructured interview schedule. The speech contents were analyzed in accordance with the Theory of Social Representations and complemented by the Central Nucleus Theory. The discussion of the results was grounded on literary findings of the companion s participation in pregnancy as well as in risk pregnancy associated with hypertensive syndromes. The data showed fear as representation s central nucleus, while recollections of that feeling referred to death of both companion and child in addition to fear of the unknown. The categories preoccupation and carefulness, other feelings, and clinical picture of the disease represented components of the peripheral nucleus. The results concerning mental images followed the same category criteria of the word free association test fear, other feelings, preoccupation, carefulness, and clinical picture of the disease. After being processed in accordance with the principles of content analysis, the statements originated three thematic unities: fear and insecurity in the presence of the companion s risk pregnancy; attitudes of carefulness to the risk pregnancy of the partner; and humanized assistance during the companion s risk pregnancy. Considering the results, the conclusion is that the partner s risk pregnancy caused by hypertensive syndromes represents, for the man, feelings of fear, preoccupation, insecurity, lack of acceptance and information, as well as attitudes of carefulness. The results reveal necessity of reorganizing the obstetric assistance with an eye to including the man as participant in the reproductive process. That demands extension of humanized carefulness to the companion with a view to make him an active coadjutor in the assistance of high-risk pregnant

Efetividade da terapia fisica descongestiva na cicatrização de úlceras venosas

A venous ulcer is the most serious clinical manifestation of chronic venous failure, and the most frequent in lower limbs, accounting for 70% of all ulcers. Patients may suffer from this infirmity for several years without healing of the lesion if treatment is inadequate. The aim of this investigation was to verify the effectiveness of decongestive physical therapy in the healing of venous ulcers. This is a quasi-experimental, interventionist study, with paired, non-probabilistic sampling, composed of 50 patients divided into two groups: control and intervention, each composed of 25 patients. Both groups were identically treated for six months with daily dressings and the latter also underwent complex physical therapy consisting of a combination of the following techniques: manual lymphatic drainage, compression bandaging, lower limb elevation, myolymphokinetic exercises and skin care. The study was approved (Protocol no. 59/2007) by the Ethics Committee of the State University of Southeast Bahia. The Mann-Whitney and Chi-square tests were applied for data analysis. After statistical analysis the patients who underwent therapy showed a statistically significant difference with respect to wound contraction starting in the second month of treatment. Compared to the control, the intervention group showed a greater reduction in both pain and edema starting in the third and fourth month of therapy, respectively. To reinforce these findings, the mean percentage of tissue present at the base of the ulcer (granulation/fibrin ratio) was calculated. The intervention group showed greater granulation at the base of the ulcer compared to the control, significant from the second month of treatment on. It was observed in this study that lymphotherapy, when compared between the intervention and control groups, accelerated the healing process, and reduced pain and edema in the affected limbs. It is expected, therefore, that these results widen scientific knowledge and we suggest that this therapy be used 78 not only to reduce lymphedema, but also as a treatment option for venous ulcers, given its easy application and low cost. The data, therefore, demonstrated the importance of basic care on the part of a multiprofessional and transdisciplinary health team involved in the healing process of these infirmities, thereby contributing to better quality of life in these individuals

Pensando o estatuto do idoso no âmbito da saúde: uma reflexão à prática da cidadania

Um envelhecer saudável compreende fundamentalmente, o atendimento de necessidades que vão além da manutenção de um bom estado de saúde física. Faz-se necessário valorizar o idoso como pessoa socialmente útil, favorecendo, direta e indiretamente, o idoso, a família e comunidade para o alcance de um estilo de vida desejável. Pautando-se nessas reflexões, a partir da importância de um estudo em que se procure avaliar até que ponto, segmentos da sociedade e o próprio idoso, conhecem os direitos deste, e com isto, procurar pontuar conceitos de cidadania, vinculando os idosos a essas práticas, tendo como ponto de partida neste estudo, a saúde, como prática muito questionada no cotidiano. Este estudo, portanto, tem como objetivo verificar o conhecimento de estudantes universitários sobre os direitos do idoso no que se refere à saúde, contemplados no Estatuto do Idoso e explorar os direitos do idoso no âmbito da saúde na concepção de estudantes universitários. Trata-se de um estudo exploratório descritivo, numa abordagem qualitativa, centrando-se na análise dos aspectos legais (jurídicos) sobre o conhecimento dos direitos do idoso no âmbito da saúde pelos estudantes e sua implicação na prática da cidadania. O estudo foi realizado na cidade de João Pessoa - Pb, estudantes universitários de diferentes cursos do Campus I da Universidade Federal da Paraiba. O instrumento utilizado para coleta de dados foi uma entrevista semi-estruturada. Os coletados foram qualitativamente, explorando-se as falas dos sujeitos, utilizando-se a técnica de análise de conteúdo temática categorial. Os resultados encontram-se apresentados em quadros e temas. A partir de diferentes artigos realizados no decorrer do curso. Diante da expressividade dos resultados encontrados nesta pesquisa, é possível afirmar que os estudantes universitários ainda conhecem pouco o direito dos idosos, em particular, no campo da saúde, mesmo os estudantes da referida área. No contexto interdisciplinar este estudo sugere ações dirigidas à população do estudo propiciando pesquisas com maior impacto na mídia dirigida tanto aos idosos como a sociedade em geral

A importância da atividade física regular como estratégia complementar na promoção de resiliência de idosas e sua importância para suas vidas

O conceito de saúde, na concepção mais abrangente, é uma condição multidimensional de bem-estar físico, psicológico e social e não apenas a inexistência de enfermidades. Os benefícios da atividade física são tão relevantes quanto os benefícios psicológicos, porque ambos contribuem para a saúde. A literatura aponta um conjunto de ligações diretas e indiretas entre a atividade física e a qualidade de vida. Apesar destes benefícios, o processo de envelhecimento é caracterizado por grandes perdas biopsicossociais, que geram várias situações de adversidades que causam preocupação e podem colocar em risco a saúde do idoso. Deste modo, surge a resiliência como um conjunto de processos sociais e intrapsíquicos, que possibilitam o desenvolvimento saudável do idoso, mesmo diante de experiências negativas. Nesta direção, observou-se a necessidade de executar uma pesquisa de conhecimento multidisciplinar conciliando a Educação Física com a Psicologia, a Medicina, a Terapia Ocupacional e a Gerontologia, com o objetivo de investigar o efeito da atividade física sobre os níveis de resiliência em mulheres idosas, bem como conhecer a importância desta atividade para suas vidas. Para tanto, realizou-se um estudo comparativo descritivo, de caráter transversal. Assim sendo, 230 mulheres idosas foram divididas em dois grupos: ativas (n=115; 65,8±5,8 anos de idade), constituído por idosas matriculadas em um programa de atividade física orientada para idosos com período de prática igual ou superior a dois anos, e sedentárias (n=115; 69,2±7,2 anos de idade). Em seguida, foram submetidas à avaliação do nível de resiliência psicológica e da aptidão física (resistência muscular de membros superiores e inferiores, flexibilidade e resistência aeróbia). As idosas ativas apresentaram valores significativamente (p=0,001) maiores do fator 3 da resiliência psicológica quando comparados àqueles do grupo de idosas sedentárias, o qual está relacionado à autoconfiança e à capacidade de adaptação a situações diversas. Não foram observadas diferenças significativas (p>0,05) entre os grupos para os demais fatores (1 e 2). Quando comparados os testes de aptidão física com o nível de resiliência psicológica moderada (n=28) e alta (n=202) do fator 3, observou- se que idosas com nível de resiliência psicológica alta apresentaram maior flexibilidade (p=0,004). E para a avaliação da percepção da importância da atividade física para as idosas foi aplicado um questionário semiestruturado. A partir da Análise de Conteúdo proposto por Bardin (2009) os resultados foram: saúde/prevenção (85%), interação (47%), autonomia (40%), alegria/felicidade (33%), resiliência (33%), lazer (15%). E para avaliar a resiliência utilizou-se a Escala de resiliência de Wagnild e Young (1993). Quanto aos níveis de resiliência os resultados demonstraram que todas idosas apresentaram alto nível. Considerando os achados do presente estudo, sugere-se o emprego da atividade física como método de intervenção para melhora da saúde mental e, por conseguinte, da resiliência psicológica na população em questão, uma vez que os resultados apontam que idosas fisicamente ativas apresentam escores de resiliência psicológica superiores àquelas estratificadas como sedentárias. O resultado desse estudo possibilitou também concluir que a importância da atividade física parece estar relacionada, na sua maioria, às características de saúde/prevenção, interação social, autonomia, resiliência, alegria/felicidade e lazer. Além disso, as mulheres do presente estudo apresentaram um alto nível de resiliência quando comparado à tabela normativa