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

Universidade Federal do Rio Grande do Norte

Aproveitamento de resíduo de beneficiamento do caulim na produção de porcelanato cerâmico

Nowadays, industries from all sectors have great concerns over the disposition of the residues generated along the productive process. This is not different in the mineral sector, as this generates great volumes of residues. It was verified that the kaolin improvement industry generates great volumes of residue basically constituted of kaolinite, muscovite mica and quartz, which are basic constitution elements to formularisations of ceramics masses to the production of covering of stoneware tiles type. This happens because the methodology applied to the improvement process is still very rudimentary, what causes a very low yield, only ¼ from all the material volume that enters the improvement process, in the end, is marketable. The disposal of this residue, in a general way, causes a very big negative environmental impact, what has justified the researches efforts aiming to find a rational solution to this problem. In this way, the intention of this present work is the utilization of this residue in the manufacture of products to high quality ceramics covering, stoneware tiles in an industrial scale. For this purpose, the influence of the addition of the residue to a standard ceramics mass used by a ceramics sector company, already established in the market, with the intention of verifying the possibility of use of this residue as the mass complementary raw material and even the possible partial or total substitution of one of the components of the mass for the raw material in evidence will be studied. To the accomplishment of this work, the kaolin improvement residue generated by an industry of exploitation and improvement of kaolin, located in the region of Equador-RN, in the levels 1,2,4,8, 16 and 32% will be added to the standard mass already used for the production of stoneware tiles. The raw materials used, kaolin residue and the standard mass, were characterized through DRX, FRX, DTA, TGA and dilatometry. After the sintering of the bodies of test, tests of water absorption, apparent porosity, post burning linear retraction, apparent specific mass and flexural strength (3 point bending) were realized to determinate the technological properties of these materials. The results show the studied residue can be considered raw material of great potential to the industry of floor and ceramics covering of the stoneware tiles type

Avaliação da espécie vegetal Croton cajucara Benth como inibidor de biocorrosão em aço carbono Aisi 1020

Actually in the oil industry biotechnological approaches represent a challenge. In that, attention to metal structures affected by electrochemical corrosive processes, as well as by the interference of microorganisms (biocorrosion) which affect the kinetics of the environment / metal interface. Regarding to economical and environmental impacts reduction let to the use of natural products as an alternative to toxic synthetic inhibitors. This study aims the employment of green chemistry by evaluating the stem bark extracts (EHC, hydroalcoholic extract) and leaves (ECF, chloroform extract) of plant species Croton cajucara Benth as a corrosion inhibitor. In addition the effectiveness of corrosion inhibition of bioactive trans-clerodane dehydrocrotonin (DCTN) isolated from the stem bark of this Croton was also evaluated. For this purpose, carbon steel AISI 1020 was immersed in saline media (3,5 % NaCl) in the presence and absence of a microorganism recovered from a pipeline oil sample. Corrosion inhibition efficiency and its mechanisms were investigated by linear sweep voltammetry and electrochemical impedance. Culture-dependent and molecular biology techniques were used to characterize and identify bacterial species present in oil samples. The tested natural products EHC, ECF and DCTN (DMSO as solvent) in abiotic environment presented respectively, corrosion inhibition efficiencies of 57.6% (500 ppm), 86.1% (500 ppm) and 54.5% (62.5 ppm). Adsorption phenomena showed that EHC best fit Frumkin isotherm and ECF to Temkin isotherm. EHC extract (250 ppm) dissolved in a polar microemulsion system (MES-EHC) showed significant maximum inhibition efficiency (93.8%) fitting Langmuir isotherm. In the presence of the isolated Pseudomonas sp, EHC and ECF were able to form eco-compatible organic films with anti-corrosive properties

Resiliência e velhice: um estudo de fatores de risco e de proteção na saúde do idoso

Resilience consists of a capacity to adapt and overcome situations of risk, from the aid of protective factors. This construct constitutes a process of preventive and multidimensional present in all stages of human development. During this development, it has been immersed in the elderly biopsychosocial changes resulting from the aging process. In this sense, there was a need for a multidisciplinary study, combining psychology, medicine, nursing, social work and gerontology in order to check the resilience, its risk factors, such as life events and health, and protection, such as self-esteem and social support. For this, we performed a descriptive exploratory study of cross-sectional nature, along with a convenience sample consisting of 65 elderly users of the public health of the district east of the city of Natal/RN, Brazil. This research allowed the collection of socio-demographic, economic, relational, physical, biological and psychological in understanding the aging process. It is observed that the studied sample socio-economic status and chronic health conditions in their own lives and their families, that demand for care and attention every day, are resilient, have faced significant losses, have positive self-esteem and social support perceived as external satisfactory. Given this multidimensional nature, the aging process deserves the attention of many professionals and health policies, seeking provide to the elderly a better living conditions and mechanisms that promote well-being and health

Aleitamento e infecções por parasitas intestinais em gestantes adolescentes e seus filhos

The exclusive breastfeeding in the first six months of life practice is essential for the health and development of children. Studies show there is in human milk protective antibodies against intestinal parasites and a relationship between the absence of breastfeeding or weaning and parasitic infections. This work was a prospective cohort study involving 34 pregnant adolescents attended school in Maternity Januario Cicco / RN and their children, to assess the influence of breastfeeding on intestinal parasites in them. Thus, the parasitic infection was investigated by examination of feces parasitological and environmental factors by use of questionnaires. The average age of the mothers studied was 16.2 years. Of these 76.4% were infected and the most prevalent species of parasites were Entamoeba histolytica/dispar (76.9%), Giardia lamblia (19.2%) and Ascaris lumbricoides (11.5%). The infected children had an average age of 5.1 months and the frequency of parasites was 61.7%. The infection was earlier detecctada with 45 days of life. The most common parasites were Giardia lamblia (40%), Entamoeba histolytica/dispar (35%), Ascaris lumbricoides (5%) and Ancylostoma (5%). The average length of exclusive breastfeeding was 2.2 months. There was an association between increased duration of exclusive breastfeeding and increased time to detection of parasites in the feces of children. There was no statistically significant correlation between the socio-economic conditions and cultural and breastfeeding. The data reinforce the importance of breastfeeding to protect the children in its first year of life

A festa do bom Jesus dos navegantes em propriá-se: história de fé, espaço das relações sociais e laços culturais

The study is a survey conducted for the Master of Social Sciences carried out in partnership between the Universidade Tiradentes-UNIT/SE and the Universidade Federal do Rio Grande do Norte (UFRN). Being a religious event, we seek to show that the religious parties generally have particular meanings for each nation or region. Amaral (1998) informs that the Brazilian parties regardless of where they occur are popular demonstrations that, as the context in which they present themselves, can dilute to crystallize, to celebrate, to ritualize or sacralize the particular social experience of the groups that do. They happen as a way to thank victories or important religious passages as Christmas, the June saints celebration, patron saints and patron saints considered. Thus, The Bom Jesus dos Navegantes party in Propriá-SE: story of faith, a space of social relations and cultural ties, is presented as our field of study because it is one of those celebrations that while celebrated in Sergipe, always on Sundays in January, by some municipalities situated along the river San Francisco, has the characteristic of overlap any others placed in town, including the one of the city's patron saint, Saint Anthony, held on June 13. Concerning the materials and methods, we opted for qualitative research and participant direct observation, using the techniques of personal notes, interviews, newspapers, websites, photos, videos and testimonials from participants and organizers, as well as references offered by experts of the area. With this research answers were sought to questions about what could keep alive the celebration of Bom Jesus dos Navegantes each year in order that this is a patron saint, not saint; the way as the investment of local government with more resources in this period, during the organization of arts festivals, has created a thread of tension with the Catholic Church promoting the religious rituals was reviewed. It was also analyzed how the sacred and profane spaces present themselves inseparable from the celebration and, finally, it was revealed that the party retains its value by preserving its tradition and making room for modernity, not weakening but suffering metamorphoses of time and space and can be seen in the social and cultural bonds wrapped by the time of religious faith

Proteção da relação de emprego sob o prisma da dignidade da pessoa humana

This work aims to show that the protection of the employment relation is one of the determining factors to respect the principle of the human dignity. The goal is initially to show the devaluation of work from antiquity to the early twentieth century, when the constitutions began to standardize protective devices. This way, the consecration of the social labor rights in the Constitution of 1988 represents the culmination of the historical achievements. This work demonstrates that such rights can not be reduced or suppressed by political conveniences, once these rights are included in the list of immutable clauses. It is displayed that to achieve the fundamental right to work is not well advised to encourage the creation of jobs that maculates the worker s dignity. The outsourced work is, therefore, a classic example of the advancement of precarious forms of contemporary labor. It is inferred that the presence of various forms of harassment results in a degradation of working environment, bringing about dire consequences on professional and personal life of the worker. Thus, decent work must be the appropriate benchmark for the creation of new jobs. It is also shown that the flexibilization of the propaganda rights by certain pressure groups has as main goal to reduce or eliminate rights, based on fallacious data depicting an increase of competitiveness and jobs. In addition, the flexibility implies a growth of the precarization of the work - a reality felt by many workers subjected to such a situation due to the unemployment phenomenon whose origin is not in the protectionism of the norms. It is necessary to expand and structure the constitutionally legitimate institutions to monitor and curb the precarized work, as well as all practices that go against the dignity of the worker. It is also shown the loss of power of the sindicates in the last few years as a consequence of the pulverization workes and the capital attacks through the productive restructure whose outsourcings and privatizations are notorious examples

Associação entre consumo alimentar e atividade física com a síndrome metabólica em mulheres na pós-menopausa

Post-menopause is characterized as the period beginning one year after the permanent cessation of menstrual cycles, which is typically related to medical disorders that, in association with Metabolic Syndrome (MS), represent a set of cardiovascular risk factors. Objective: To assess dietary intake and the prevalence of metabolic syndrome in postmenopausal women, according to the level of physical activity. Methods: The sample consisted of 82 women, evaluated in the Northern Zone of the city of Natal / RN who were participants in the Natal Active Program. People completed a Food Frequency Consumption Questionnaire (FFCQ) and were interviewed about physical activity. Anthropometric measurements and biochemical tests were used to diagnose MS (Metabolic Syndrome). Result: The active women consumed more protective foods (flaxseed, nuts, whole wheat bread, brown rice and olive oil) than inactive women. Risky foods (sugar, crackers, white bread, white rice, margarine and beef) were consumed more by the group of inactive women. The prevalence of MS was higher in inactive women (53.30%) than in physically active women (46.70%). Conclusion: Active post-menopausal women had a higher daily intake of protective foods in relation to cardiovascular disease, while the inactive post-menopausal women had higher intake of risky foods for such diseases

Argamassas do grupo escolar Augusto Severo/RN: caracterização e incidência de manifestações patológicas

The search for cultural heritage preservation should be a constant, in order to minimize the lost of historical and cultural identity of a country. As part of this cultural heritage, highlights the importance of historical buildings. For the principles of restoration are met its important to know the state of conservation and the existing materials. Given the above, this work aims to study the pathological manifestations of the mortar coating from the Grupo Escolar Augusto Severo. For this, was conducted historical survey of the building, on-site visits with visual observation, collecting samples of mortar coating and characterization through visual and laboratory analysis, XRF, XRD, TG/DTG, OM and SEM-EDS. From the observations, pathological manifestations were found as: cracks, detachment of the coating, dirt, use of inappropriate material basis of cement, efflorescence, mold and mildew and also incompatible material base of cement. It was found that the pathological manifestations were intensified due to lack of coverage in some spots and especially the abandonment of the building, that many years does not have restoration or any other type of preventive and corrective maintenance. The results of laboratory tests indicated that the mortars studied are based on lime, with calcitic nature, and siliceous aggregate, with the presence of clay in two samples. From the samples collected, two are composed of lime, sand and clay and two by lime and sand. In this regard, it is important to conduct periodic inspections and maintenance, as well as carrying out restoration with use of material compatible with the original

Obtenção de placas cerâmico a partir de formulações de massas triaxiais de resíduos de caulim, chamote de telha e cinza vegetal

The production of red ceramic is an industrial activity that causes an intense impact. The manufacture of its products considerably increases the demand for natural resources, mainly with the extraction of raw material. The ceramic material produced generates waste, such as ash firewood and chamote. The residue from the beneficiation of kaolin is deposited in a poor, degrades the environment and contaminate water sources and soil, constituting in this manner, ecological disasters. The main objective of this work is to develop the formulation of a ceramic product consisting solely of industrial solid wastes, from ceramic tiles, (chamote) residue of kaolin and ash firewood. It is assumed that this product made in the laboratory can be used in coatings, wall and floor. The aim is to facilitate the replacement of the raw material of original composition of a ceramic body, for waste, while the process of production equal to the conventionally used, so that the properties of the product are reproduced. This work is characterized waste as its chemical composition, analysis of particle size, X-ray diffraction and thermal behavior. Several formulations were studied. The mass of waste was prepared by dry process, pressed to 25 MPa, and then burned in muffle type oven to 850, 950, 1050 and 1150 °C. The results showed that it is technically possible to produce porous tiles only with waste. It was found that the formulations of bodies play a key role in the properties of the final product, as well as the sintering temperature and heating rates. RN in the waste of kaolin is estimated at 15,000 t/month, about 3,000 gray t/month and chamote with 10 million pieces/month damaged. The presence of carbonates of calcium and magnesium at 1050 ° C results in an appropriate porosity and mechanical strength. The formulation M3JE, composed of 69% waste of kaolin, 7.7% and 23.3% of chamote of gray, became suitable for porous materials with the strength and absorption within the level of national and international standards

Caracterização de matérias-primas regionais e desenvolvimento de formulações de massas cerâmicas para porcelanato

Initially concentrated in some poles at the South and Southeast regions of Brazil, the ceramic tiles industry became wide during the 80 s decade, with a disconcentration industrial and regional pulverization. The competitiveness in the ceramic tiles internal and external consumers markets, it has debtor the industries to invest in sophisticated products each time more, either in design or the technology, but, mainly, in its final properties. Amongst the diverse types of ceramic coating, the porcelanato if has detached had to its process of technological production and excellent characteristics techniques. The Porcelanato is currently the material for coatings that presents the best technical and aesthetic features when compared with others ceramics found on the market. The chemical composition and the others raw materials characteristics have an importance that must to be ally to the inherent characteristics of fabrication process, essentially those related to the cycle of burning. This work had as purpose to develop formularizations of ceramic mass for production of porcelanato without glass coating, pertaining to the group BIa (text of absorption of water ≤ 0.5%) and with resistance superior mechanics 35MPa from raw materials characterized. The ceramic raw materials selected to the development of this study (A1 and A2 clays, feldspate, talc and quartz) were submitted to the following tests: X-ray fluorescence - chemical analysis determination; X-ray diffraction - Analysis of the stages mineralogics; Laser granulometry - size distribution of particles; and Differential thermal analysis - thermal behavior. Were performed tests of absorption of water, lineal retraction of it burns, apparent specific mass and rupture tension the flexing. The results had evidenced that the formularizations that had the A1 clay and talc on its composition were efficient for the porcelanato production remaining their technological characteristics inside of the intervals of variation desired by the Norms of the ABNT

Desenvolvimento e caracterização de nanocompósito de resina epóxi com nanopartículas de sílica para revestimento de dutos para transporte de petróleo

The use of polymer based coatings is a promising approach to reduce the corrosion problem in carbon steel pipes used for the transport of oil and gas in the oil industry. However, conventional polymer coatings offer limited properties, which often cannot meet design requirements for this type of application, particularly in regard to use temperature and wear resistance. Polymer nanocomposites are known to exhibit superior properties and, therefore, offer great potential for this type of application. Nevertheless, the degree of enhancement of a particular property is greatly dependent upon the matrix/nanoparticle material system used, the matrix/nanoparticle interfacial bonding and also the state of dispersion of the nanoparticle in the polymer matrix. The objective of the present research is to develop and characterize polymer based nanocomposites to be used as coatings in metallic pipelines for the transportation of oil and natural gas. Epoxy/SiO2 nanocomposites with nanoparticle contents of 2, 4, and 8 wt % were processed using a high-energy mill. Modifications of the SiO2 nanoparticles‟ surfaces with two different silane agents were carried out and their effect on the material properties were investigated. The state of dispersion of the materials processed was studied using Scanning and Transmission Electron Microscopy (SEM and TEM) micrographs. Thermogravimetric analysis (TG) were also conducted to determine the thermal stability of the nanocomposites. In addition, the processed nanocomposites were characterized by dynamic mechanical analysis (DMA) to investigate the effect of nanoparticles content and silane treatment on the viscoelastic properties and on the glass transition temperature. Finally, wear tests of the pin-on-disc type were carried out to determine the effects of the nanoparticles and the silane treatments studied. According to the results, the addition of SiO2 nanoparticles treated with silane increased the thermal stability, the storage modulus and Tg of the epoxy resin and decreased wear rate. This confirms that the interaction between the nanoparticles and the polymer chains plays a critical role on the properties of the nanocomposites

Efeito de adições poliméricas na aderência de pastas de cimento a tubos metálicos após ciclagem térmica

Thermal recovery methods, especially steam injection, have been used to produce heavy oils. However, these methods imply that the metallic casing-cement sheath interface is submitted to thermal cycling. As a consequence, cracking may develop due to the thermal expansion mismatch of such materials, which allows the flow of oil and gas through the cement sheath, with environmental and economical consequences. It is therefore important to anticipate interfacial discontinuities that may arise upon Thermal recovery. The present study reports a simple alternative method to measure the shear strength of casing-sheath interfaces using pushthrough geometry, applied to polymer-containing hardened cement slurries. Polyurethane and recycled tire rubber were added to Portland-bases slurries to improve the fracture energy of intrinsically brittle cement. Samples consisting of metallic casing sections surrounded by hardened polymer-cement composites were prepared and mechanically tested. The effect of thermal cycles was investigated to simulate temperature conditions encountered in steam injection recovery. The results showed that the addition of polyurethane significantly improved the shear strength of the casing-sheath interface. The strength values obtained adding 10% BWOC of polyurethane to a Portland-base slurry more than doubled with respect to that of polyurethane-free slurries. Therefore, the use of polyurethane significantly contributes to reduce the damage caused by thermal cycling to cement sheath, improving the safety conditions of oil wells and the recovery of heavy oils

Modificação superficial do tecido 100% algodão tratado com plasma

The 100% cotton fabric (CO)* treated with plasma of methane CH4 has direct application in all areas that needs of aqueous solutions repellent material like coatings and uniforms applied biomedical, aeronautics, and automobile between others. 100% cotton fabric (CO) samples were treated by plasma with two differents atmosphere: Methane gas (CH4), treatment time was varied in 10 in 10 min. until 60 min., and mixture methane/argon (CH4/Ar), it was varied the proportion 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, with treatment time of 30 minutes. In both, the fluxe was 5 sccm (second cubic centimeter), pressure 6 mbar, voltage 490 V and current 0,15A. The objective of work was measure the superficial tension of 100% CO then it treated with plasma, using contact angle measures of water and glycerol with the surface. The samples were tested after treatment, with 8 and 12 months to verify the superficial modification effects. It was verified an increase of hydrophobility with the Sessile drop values varied between 116,69º to 137,85º and it carried on after 12 months. The no treated samples shows contact angle equal 0º. OES analysis and Raman spectroscopy were accomplished. In the SEM analysis was verified oligomers. The plasma treatment is correct environmental, It turning greater than conventional treatments

Estudo do potencial de utilização do resíduo da extração de esmeraldas na fabricação de cerâmica de revestimento

Companies involved in emerald mining and treatment represent an important area of industrial development in Brazil, with significative contribution to the worldwide production of such mineral. As a result, large volumes of emerald waste are constantly generated and abandoned in the environment, negatively contributing to its preservation. By the other side the interest of the use of mining waste as additive in ceramic products has been growing from researchers in recent years. The ceramic industry is constantly seeking to the marked amplification for the sector and perfecting the quality of the products and to increase the variety of applications. The technology of obtaining of ceramic tiles that uses mining residues assists market niches little explored. In this scenario, the objective of the present study was to characterize the residue generated from emerald mining as well as to assess its potential use as raw material for the production of ceramic tiles. Ceramic mixtures were prepared from raw materials characterized by X-ray fluorescence, X-ray diffraction, particle size analysis and thermal analysis. Five compositions were prepared using emerald residue contents of 0%, 10%, 20%, 30% and 40%. Samples were uniaxially pressed, fired at 1000, 1100 and 1200ºC and characterized aiming at establishing their mineralogical composition, water absorption, apparent porosity, specific mass, linear retraction and modulus of rupture. The results shows that the emerald residue, basically consisted of 73% of (SiO2 + Al2O3) and 17,77% of (MgO + Na2O+ K2O) (that facilitates sintering), can be added to the ceramic tile materials with no detrimental effect on the properties of the sintered products