Estudo de um compósito de matriz cerâmica com carga de recicláveis para o uso na construção civi

With a view to revitalizing public environments through criteria that include economy, tourism, aesthetics and respect for the environment, this paper proposes a model of kiosk manufactured with composite material blocks, to be employed as a public instrument. . The model consists of a structure composed of planned blocks and manufactured in cement-based composite, gypsum, ground and water, having the styrofoam inside filled with pet bottles of 500 ml dose. The social and environmental issue is the critical point of the work when it can, through the reuse of environmentally harmful materials such as polyethylene terephthalate PET, using such modules for the construction of various areas of Commerce, promoting the protection of the environment combined with the improvement of the quality of life of the population. The tourism factor, which is significant in the economy of the North, is also considered as the modulated kiosk has a visual aspect innovative and differentiated. The environmental issue is addressed by encouraging the reuse of PET material and EPS (polystyrene)

PET containers in Brazil: Opportunities and challenges of a logistics model for post-consumer waste recycling

The use of post-consumer materials is directly related to reducing the cost of production and extraction of natural resources. Non-recyclable materials are randomly disposed in the environment. Brazil is one of the largest consumers of PET (polyethylene terephthalate) bottles. The purpose of this paper is to describe the opportunities and challenges of the logistics model for post-consumer PET bottle recycling in Brazil, while providing knowledge of its practices along the recycling chain. The results describe the need to educate those directly and indirectly involved in the process: to reduce consumption in order to reduce the amount of waste generated: to structure the post-consumer reverse chain and engage industrial sectors and government, through public policies, to support cleaner technologies along the PET bottle production chain. (C) 2010 Elsevier B.V. All rights reserved.

Treatment of PET and PU polymers by atmospheric pressure plasma generated in dielectric barrier discharge in air

Plasma treatments are frequently employed to modify surface properties of materials such as adhesivity, hydrophobicity, oleophobicity etc. Present work deals with surface modification of common commercial polymers such as polyethylene terephthalate (PET) and polyurethane (PU) by an air dielectric barrier discharge (DBD) at atmospheric pressure. The DBD treatment was performed in a plain reactor in wire-duct geometry (non-uniform field reactor), which was driven by a 60 Hz power supply. Material characterization was carried out by water contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The plasma-induced modifications are associated with incorporation of polar oxygen and nitrogen containing groups on the polymer surface. The AFM analysis reveals that the plasma treatment roughens the material surface. Due to these structural and morphological changes the surface of DBD-treated polymers becomes more hydrophilic resulting in enhanced adhesion properties. (C) 2010 Elsevier B.V. All rights reserved.

Wettability of Aqueous Rhamnolipids Solutions Produced by Pseudomonas aeruginosa LBI

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito do cloreto de cálcio na qualidade de melancias minimamente processadas

Foi avaliada a qualidade de melancias minimamente processadas, tratadas com cloreto de cálcio, durante o armazenamento sob refrigeração. Utilizaram-se melancias 'Crimson Sweet', maduras, adquiridas no comércio de Piracicaba, SP, oriundas do Rio Grande do Sul. Os frutos foram lavados e desinfetados com água clorada (200 mg L-1). A polpa foi cortada em cubos (2,5 cm de aresta), os quais foram imersos, por 3 min nas soluções que corresponderam aos tratamentos, imersão em água pura (controle), solução de cloreto de cálcio a 1%. em seguida foram escorridos por 3 min, acondicionados em copos de tereftalato de polietileno (PET) transparente de 450 mL de capacidade, com tampa, e armazenados sob refrigeração a 10,0 ± 3,2°C e 79% UR. A cada dois dias, os pedaços foram avaliados sensorialmente e quanto à perda de massa fresca, aparência, coloração interna, textura, teores de sólidos solúveis (SS) e de acidez titulável (AT), pH, relação SS/AT e conteúdos de ácido ascórbico e de pectinas, solúvel e total. O uso da solução de cloreto de cálcio promoveu maior firmeza na textura de melancias minimamente processadas, porém não se mostrou efetivo no prolongamento da vida útil, que foi de 2 dias do ponto de vista sensorial.

Determinação da variação da viscosidade intrínseca do poli (tereftalato de etileno) de embalagens

O mercado de embalagens de poli(tereftalato de etileno) -PET- para acondicionamento de refrigerantes, água mineral, sucos concentrados e óleos comestíveis apresenta polímeros de diferentes tipos, que foram desenvolvidos para personalizar o atendimento a clientes desejosos de propriedades melhores e mais específicas, principalmente em termos de massa molar. No caso do PET, assim como na indústria da reciclagem do polímero, o ensaio de viscosidade intrínseca é muito usado para determinar a massa molar. Este trabalho apresenta os resultados de viscosidade intrínseca de PET advindo de embalagens de várias marcas de refrigerantes, sucos e óleos de soja. Amostras de cada embalagem foram dissolvidas em solução de fenol-tetracloroetano (60:40 em peso) e o fluxo das mesmas em um viscosímetro Cannon-Fenske a 30 °C para medir a viscosidade relativa, que foi convertido para viscosidade intrínseca. Os resultados mostraram uma variação no valor da propriedade conforme se variava o volume, tipo e a marca do produto envasado. Para as 21 amostras analisadas, os resultados variaram de 0,70 a 0,79 dL/g. Portanto, uma melhor seleção das embalagens pode ajudar os recicladores na obtenção de produtos melhores, com menor variação na massa molar. Os valores de densidade obtidos apresentaram uma pequena variação, que torna-se maior quando transformados em cristalinidade.

Recycling potential of urban solid waste destined for sanitary landfills: the case of Indaiatuba, SP, Brazil

The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of São Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000 kg day(-1). A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks.

Effect of cold plasma treatment on mechanical properties of PET/PMMA composites

Mechanical strength of polyethylene terephthalate (PET) fibres and polymethyl methacrylate (PMMA) matrix composites were studied with particular interest on the effects of oxygen and argon plasma treated fibres. PET. fibres were treated in a radio frequency plasma reactor using argon or oxygen for different treatment times to increase the interface adhesion. Fibre volume fraction was measured through digital image analysis. Elastic moduli resulted between 3 GPa for untreated to 6 GPa for treated composites. Tensile tests on PET fibres showed that plasma treatment caused a decrease in average tensile strength compared to untreated fibres. Fracture analysis confirmed the increase in interfacial adhesion due to plasma treatment. (c) 2004 Elsevier Ltd. All rights reserved.

Production and preservation of fresh-cut 'Tommy Atkins' mango chunks

During the 1999/00 and 2000/01 seasons, sliced 'Tommy Atkins' mangoes were packaged with three different types of polymeric films; polypropylene (PP) cups, low-density polyethylene (LPDE) bags or polyethylene terephthalate (PET) clamshell trays, and stored at 3°C for 2 weeks. The mango chunks were evaluated for flavor, appearance, colour, total soluble solids (TSS), total titratable acidity (TTA), ascorbic acid (AA) contents, O2 and CO 2 concentration in the packages, as well as respiration. Shelf life based on visual appearance was 14 days, with the products showing good appearance and agreeable aroma. The TTA content in chunks packaged in PP cups or PET trays were reduced during the storage, and with the color changing from light yellow to dark yellow. The chunks respiration in PP cups or LPDE bags were 64.6 and 87.9 mL CO2.kg-1.h-1, and in PP cups or PET trays were 45.86 and 43.92 mL CO2.kg-1.h -1, respectively for 1999/00 and 2000/01 seasons. The percentages of O2 and CO2 in the packages were stabilized after 2-4 hours, and the atmosphere had 11-17% and 1-10% of them. The microbiological content was lower than the allowed. No differences were observed between the seasons, and the best packages were the cups.

Aderência e formação do biofilme por Staphylococcus aureus ao polietilenotereftalato (PET) usado como embalagem para acondionamento de medicamentos e cosméticos

The polyethylene terephthalate (PET) is used for package drugs and cosmetics. The aim of this research was examine by scanning electron microscopy (SEM) a Staphylococcus aureus attachment and biofilm formation on a polyethylene terephthalate (PET) surface and hydrophobicity of S. aureus by adherence to hydrocarbons. A suspension of S. aureus was prepared in Mueller-Hinton broth and, coupons of polyethylene terephthalate were incubated for 30 minutes, two, 24 and 48 hours, 15 and 30 days. Afteron the coupons were removed and prepared for scanning electron microscope analysis. The attachment and biofilm formation was observed on the surfaces of PET. The SEM revealed adhesion and biofilm formation on PET surfaces. The hydrophobicity test classified S. aureus as hydrophobic.

Respiratory and storage behavior of fresh cut 'Tommy Atkins' mango

The respiratory and storage behavior of fresh cut 'Tommy Atkins' mango, naturally ripened (NR) or with use of ethylene (RE), were studied. Fruits were selected, washed and disinfected (200 mgCl.L-1) and stored for 12 hours at 10°C. After this period, they were processed under hygienic conditions at 10°C, packaged in polyethylene terephthalate (PET) trays or in styrofoam trays wrapped with stretchable polyvinyl chloride (PVC) film and stored for up to 15 days at 3°C. The products were evaluated regarding the evolution of internal atmosphere in the packing (O2 and CO 2), development of weight, appearance, shelf life and consumer acceptability. The respiratory rate was measured before and after processing every two hours. The yield of 'Tommy Atkins' mango to produce fresh cut product was 48.09±0.95%. Increase of the respiration rate of both mango samples was verified one hour after the preparation (NR = 17.75 mL CO 2.kg-1.h-1; RE = 28.29 mL CO 2.kg-1.h-1), followed by stabilization at 3.76 and 8.07 mL CO2/kg.h, respectively. The percentage of O2 in packages was stable in all treatments, 15-20% in PVC trays, 18-20% in PET tray. The percentage of CO2 was steady around 1.5-2.5%. The products lost fresh mass during the storage, from 0.06% to 0.30% for PET trays and from 0.15% to 1.61% for trays covered with PVC. The appearance was considered appropriate for commercialization until the 13th day, whereas product from mangoes ripened with application of ethylene was for 11 days, presenting browning in the external surface. The naturally ripened mango presented the best flavor and consumer preference in relation to the mango ripened with application of ethylene for 11 days of storage. The control of hygienic conditions during the production and storage was good and with safety for until 10 days.

Use of modified atmosphere to extend shelf life of fresh-cut carambola (Averrhoa carambola L. cv. Fwang Tung)

Fresh-cut fruit products, including carambola (Averrhoa carambola L.) have limited marketability due to cut surface browning attributed to oxidation of phenolic compounds by enzymes such as polyphenol oxidase (PPO). The objective of this study was to evaluate postharvest changes of carambola slices in three different packagings. Carambola fruit (cv. Fwang Tung) were picked from the orchard of Estação Experimental de Citricultura de Bebedouro at mature-green stage. Fruit were washed, dipped in NaOCl solution (200 mg.L -1 for 5 minutes), and stored overnight at 10°C. Fruit were manually sliced into pieces of approximately 1 cm. Slices were rinsed with NaOCl solution at 20 mg.L-1, drained for 3 minutes, and packaged in polyethylene terephthalate (PET) trays (Neoform N94); polystyrene trays covered with PVC 0.017 mm (Vitafilm - Goodyear); and vacuum sealed polyolefin bags (PLO, Cryovac PD900). The packages were stored at 6.8°C and 90%RH for 12 days and samples taken every 4 days. PET trays and PVC film did not significantly modify internal atmosphere and the high water permeability of PVC led to more rapid slice desiccation. PPO activity was lower when slices were packaged in PLO vacuum sealed bags, which reduced discolouration and led to better appearance maintenance for up to 12 days.

Estádios de maturação de pêssegos 'Aurora-1' para o processamento mínimo

The experiment aimed to verify the effect of maturation stage on the quality of minimally processed peaches. Fruits were used in two stages of maturity, on time corresponding to the background color yellow-green, and mature, which corresponds completely to the background color yellow. The minimum process consisted of washing, sanitizing, enzyme peel, cut lengthwise and removed the stone fruits. Halves obtained were immersed in water chlorinated to 10 mg L-1 of water and left on standing to drain the excess liquid. Afterwards, it was proceeded the packaging of the halves in containers of polyethylene terephthalate (PET) and with transparent lid, and the storage at 3 ± 2 ° C and RH = 65% for 12 days, with assessments every three days. The variables evaluated were appearance, weight loss, firmness, soluble solids, titratable acidity, soluble and reduced sugars, ascorbic acid, total and soluble pectin, coloring and activity of polyphenoloxidase. The storage of minimally processed peaches 'Aurora-1' mature harvested was limited mainly by the loss of freshness and firmness, and because they have darker appearance, and lower levels of reduced sugars and ascorbic acid. Peaches 'Aurora-1', harvested at the maturity stage on time, had better quality and longer duration of their minimally processed products.

Influência da paralisação escalonada da aeração na eficiência do tratamento aeróbio na manipueira em batelada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)