Revestimentos cerâmicos: acima e além das aplicações tradicionais

Nos últimos anos os revestimentos cerâmicos têm seguido a mesma tendência de inúmeros outros produtos dos chamados setores industriais tradicionais: a busca de novos usos e aplicações, que permitam ampliar seus mercados usuais. Na verdade, isto não é surpresa, pois as características dos materiais cerâmicos permitem múltiplas aplicações. Um exemplo neste sentido são as ?cerâmicas técnicas?; estes materiais cerâmicos têm sido utilizados há anos em áreas relacionadas à alta tecnologia, dado o seu excelente desempenho técnico - especialmente em comparação com outros materiais, como os metais, que há muito tempo têm definido o padrão de desempenho na área de materiais. Entretanto, apesar dos revestimentos também serem produtos cerâmicos, não têm o perfil ou a ?aura? tecnológica de um produto do futuro, característica típica das cerâmicas ?técnicas? ou ?avançadas?. No entanto, as evidências são contrárias a essa impressão superficial. Atualmente os revestimentos cerâmicos já estão sendo comercializados com características e desempenho que os tornam produtos cujas aplicações vão muito além de seu uso convencional. Deve-se perceber, além disso, que estas não são apenas possibilidades futuras: sua realidade industrial e comercial já os torna imediatamente utilizáveis em vários ambientes. E este é precisamente o conceito-chave para as novas aplicações dos revestimentos: as suas características os tornam utilizáveis para funções completamente diferentes ? funções até agora reservadas a outros produtos ? ou, em certos casos, para funções totalmente novas. Além disso, as funcionalidades envolvidas são destinadas a melhorar aspectos diretamente relacionados com a qualidade de vida e com condições de habitabilidade, ou, por exemplo, para utilizar uma fonte natural de energia tão vital como a radiação solar. Deve-se, portanto, salientar que estas novas gerações de revestimentos cerâmicos devem ser consideradas como parte de um conjunto de elementos arquitetônicos para usos externos e internos, pois, como será visto, eles proporcionam às superfícies que revestem uma ampla gama de propriedades e funções, sem prejuízo das qualidades estéticas, sempre tão características dos revestimentos cerâmicos. Para ilustrar o exposto, o presente artigo descreve três novas famílias de produtos cerâmicos. Estes grupos de produtos são conceitualmente diferentes e multifacetados, o que os tornam úteis como elementos funcionais em diferentes contextosIn recent years, ceramic tiles have followed the same trend of many other products of the so-called traditional industries: the search for new uses and applications that can widen their usual markets. In fact, this is not surprising, since the characteristics of ceramic materials enable multiple applications. An example of this is technical ceramics. These ceramic materials have been used for years in areas related to high technology, given its excellent technical performance, especially if compared to other materials such as metals that have long defined their performance in the materials area. However, despite of the fact that coatings are also ceramic products, they do not have the profile or technological popularity of a product from the future, a typical characteristic of most technical or advanced ceramics. However, evidences are contrary to this first impression. Nowadays, ceramic tiles are being marketed with features and performance that make them products whose applications go far beyond their conventional use. One should realize, moreover, that these are not just future possibilities: their industrial and commercial reality already makes them readily usable in different environments. And this is precisely the key concept for the new applications of coatings: their characteristics make them usable for completely different functions —functions which were formerly reserved for other products— or, in some cases, for completely new functions. Moreover, the features involved are aimed at improving aspects directly related to quality of life and living conditions, or, for example, to use a natural source of energy as vital as solar radiation. It should therefore be stressed that these new generations of ceramic tiles should be considered as part of a set of architectural elements to external and internal uses, for, as we will see, they provide to the surfaces a wide range of properties and functions without prejudice to the aesthetic qualities, always so characteristic of ceramics. To illustrate the above, this article describes three new families of ceramic products. These groups of products are conceptually different and multifacete

Automatización de un Sistema Multiplataforma de Control y Monitoreo de Riego Tecnificado para el Distrito de los Palos en el Año 2017

La presente tesis fue realizada y desarrollada bajo la línea de investigación de las TIC´s para una mejora continua de las actividades que realizan las organizaciones del Perú, de la Escuela Profesional de Ingeniería de Sistemas de la Universidad Privada de Tacna, el cual tuvo como principal objetivo realizar la Automatización de un sistema multiplataforma de control y monitoreo de riego tecnificado para el distrito de los palos en el año 2017, el cual tiene como principal objetivo mejorar el tiempo de trabajo, así como también el ahorro del agua. Esta investigación corresponde al tipo aplicado puesto que gracias a esta se logrará obtener nuevos conocimientos en base a la problemática descrita. De acuerdo a la metodología la clasificación que se utilizó para el diseño de la investigación, es una investigación Transversal Correlacional y Comparativa, esto por las características que la investigación mostró.Tesi

Antimicrobial activity of Enterococcus faecium FAIR-E 198 against gram-positive pathogens

This study investigated the antimicrobial activity of Enterococcus faecium FAIR-E 198 against Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus. Using the critical-dilution method, the bacteriocin produced by E. faecium FAIR-E 198 inhibited all L. monocytogenes strains evaluated (1,600 to 19,200 AU mL-1). However, none of the B. cereus and S. aureus strains investigated were inhibited. The maximum activity of this bacteriocin (800 AU mL-1) was observed in MRS broth, while the activity in milk was 100 AU mL-1. In the co-cultivation test in milk, B. cereus K1-B041 was reduced to below the detection limit (1.00 log CFU mL-1) after 48 h. E. faecium reduced the initial L. monocytogenes Scott A population by 1 log CFU mL-1 after 3 h at 35ºC. However, the pathogen regained growth, reaching 3.68 log CFU mL-1 after 48 h. E. faecium did not influence the growth of S. aureus ATCC 27154 during the 48 h of co-cultivation. Therefore, it can be concluded that the effectiveness of the antimicrobial activity of E. faecium FAIR-E 198 is strictly related to the species and strain of the target microorganism and to the culture medium.7481Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Antimicrobial Activity Of Enterococcus Faecium Fair-e 198 Against Gram-positive Pathogens.

This study investigated the antimicrobial activity of Enterococcus faecium FAIR-E 198 against Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus. Using the critical-dilution method, the bacteriocin produced by E. faecium FAIR-E 198 inhibited all L. monocytogenes strains evaluated (1,600 to 19,200 AU mL(-1)). However, none of the B. cereus and S. aureus strains investigated were inhibited. The maximum activity of this bacteriocin (800 AU mL(-1)) was observed in MRS broth, while the activity in milk was 100 AU mL(-1). In the co-cultivation test in milk, B. cereus K1-B041 was reduced to below the detection limit (1.00 log CFU mL(-1)) after 48 h. E. faecium reduced the initial L. monocytogenes Scott A population by 1 log CFU mL(-1) after 3 h at 35°C, However, the pathogen regained growth, reaching 3.68 log CFU mL(-1) after 48 h. E. faecium did not influence the growth of S. aureus ATCC 27154 during the 48 h of co-cultivation, Therefore, it can be concluded that the effectiveness of the antimicrobial activity of E. faecium FAIR-E 198 is strictly related to the species and strain of the target microorganism and to the culture medium.4174-8

Mechanical properties obtained by nanoindentation of sintered zircon-glass matrix composites

This study was undertaken to determine the effect of zircon content and firing temperature on the hardness and indentation modulus of zircon–glass composites obtained by sintering. A standard non-devitrified borosilicate glass (SRM 717a) powder and an industrial micrometric zircon powder were used to prepare mixtures with a zircon volume/solids volume between 0 and 0.63, by the wet method. The values of these mechanical properties were determined by nanoindentation and related to the most important microstructural characteristics of the composites, such as porosity, zircon volume fraction, glass volume fraction, and average zircon grain size. Composite mechanical performance was interpreted and determined by statistically analysing the results of a large number of indentations using two maximum loads. An empirical model was developed that describes the effect of these microstructural characteristics on composite hardness and modulus of indentation. Composites of high hardness (11.3 ± 2.5 GPa) and low porosity (ε = 0.07) were obtained at 1100 °C from a mixture with a zircon volume/solids volume of 0.43

Desenvolvimento de vidrados cerâmicos com propriedades bactericidas e fungicidas

Nos últimos anos foram desenvolvidas técnicas que permitem a síntese de materiais que, ao menos em uma de suas dimensões, são de tamanho nanométrico (1 a 100 nm), apresentando assim propriedades e funções significativamente diferentes das observadas nos materiais tradicionais de tamanho micrométrico. Os nanomateriais têm uma ampla faixa de aplicações especiais, especialmente em eletrônica, ciência dos materiais, comunicações e sistemas biológicos. As análises econômicas indicam que o mercado de nanotecnologia movimentará entre 750 milhões e 2 bilhões de euros a partir de 2015. No entanto, no setor cerâmico ainda não se começou a trabalhar com nanomateriais, pois as potenciais vantagens destes materiais ainda não foram valoradas convenientemente. É o que ocorre com as propriedades antimicrobianas que determinados nanomateriais podem aportar aos revestimentos cerâmicos. A aparição desta nova geração de materiais pode permitir a obtenção de produtos cerâmicos com propriedades bactericidas e fungicidas, cujas superfícies sejam capazes de impedir e eliminar o crescimento de organismos patogênicos, mantendo deste modo as melhores condições de segurança e higiene ambiental. Com isto, o setor cerâmico pode desenvolver produtos inovadores, de maior qualidade e alto valor agregado, com objetivo de aumentar sua competitividade.Este trabalho foi realizado graças ao apoio do Conselho da Indústria, Comércio e Navegação da Generalitat Valenciana, através do IMPIVA (n° de expediente IMIDIC/2009/10) e do Fundo Europeu de Desenvolvimento Regional

UM OLHAR SOBRE A LEITURA DE BEST-SELLER

 This work intends to discuss the "bestseller" concept, relating aspects on the cultural industry and concluding with the performance analysis of a well-know bestseller Brazilian writer, Luís Fernando Veríssimo. The handling of the reading process will be based following the discourse analysis from the Parisian school of semiotics aiming to verify the reasons from which this type of discourse is widely acquired by the contemporary Brazilian reader. Este trabalho pretende discutir a noção de best-seller, tangenciando aspectos da indústria cultural e culminando com a ilustração da performance de luís fernando veríssimo, escritor responsável por livros de sucesso no mercado editorial brasileiro. O tratamento da questão da leitura está assentado na perspectiva da análise do discurso, segundo orientação da semiótica da escola de paris, e seu principal objetivo consiste em verificar as razões pelas quais esse tipo de discurso é bastante consumido pelo leitor brasileiro contemporâneo

Non-isothermal sintering of powdered vitrified composites. A kinetic model

This report sets out the results obtained on studying the sintering process of glass–zircon composites, analysing the microstructural changes that developed on modifying zircon content. The sintering of composites with moderate zircon contents only developed via particle rearrangement by viscous flow. In contrast, at high zircon contents, the zircon solution–reprecipitation process was also required. A kinetic model was developed and validated that describes the effect of the heating rate and zircon volume fraction on the composite degree of non-isothermal sintering progress associated with particle rearrangement by viscous flow

Software tool for simulation of aircraft trajectories

New concepts in air navigation have been introduced recently. Among others, are the concepts of trajectory optimization, 4D trajectories, RBT (Reference Business Trajectory), TBO (trajectory based operations), CDA (Continuous Descent Approach) and ACDA (Advanced CDA), conflict resolution, arrival time (AMAN), introduction of new aircraft (UAVs, UASs) in air space, etc. Although some of these concepts are new, the future Air Traffic Management will maintain the four ATM key performance areas such as Safety, Capacity, Efficiency, and Environmental impact. So much, the performance of the ATM system is directly related to the accuracy with which the future evolution of the traffic can be predicted. In this sense, future air traffic management will require a variety of support tools to provide suitable help to users and engineers involved in the air space management. Most of these tools are based on an appropriate trajectory prediction module as main component. Therefore, the purposes of these tools are related with testing and evaluation of any air navigation concept before they become fully operative. The aim of this paper is to provide an overview to the design of a software tool useful to estimate aircraft trajectories adapted to air navigation concepts. Other usage of the tool, like controller design, vertical navigation assessment, procedures validation and hardware and software in the loop are available in the software tool. The paper will show the process followed to design the tool, the software modules needed to perform accurately and the process followed to validate the output data

Sinter-crystallisation kinetics of a SiO2–Al2O3–CaO–MgO–SrO glass-ceramic glaze

This paper examines the microstructural development and kinetics of the sintering and crystallisation processes of a SiO2–Al2O3–RO (R = Ca, Mg, Sr) glass-ceramic glaze. Crystallisation and sintering kinetics were studied by DTA and HSM, respectively, at different heating rates. The kinetic parameters of crystallisation were determined by the usual methods (Kissinger, Kissinger-Akahira-Sunose, Ozawa and Augis-Bennet methods), and the Johnson–Mehl–Avrami–Kolmogorov (JMAK) model, with an Avrami index of n = 3, characteristic of the surface crystallisation of very fine glass particles, was found to describe crystallisation kinetics very well. Sintering could also be described by the JMAK model, but with n < 1. Assuming the effect of temperature on the sintering rate to be the same as that of this variable on the inverse of glass matrix viscosity, a model was developed, based on the JMAK model, which only required a single fitting parameter. As the heating rate increased, the degree of overlap between the sintering and crystallisation processes was verified to decrease