Development of a Yellow Pigment Based on Bismuth and Molybdenum-Doped TiO2 for Coloring Polymers

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Development of a new clean methodology with ultrasound-assisted extraction for analysis of sodium in pet foods

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Polyacrylic acid polymers hydrogels intended to topical drug delivery: preparation and characterization

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efficiency comparison of hyperbranched polymers as toughening agents for a one-part epoxy resin

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

Strategies to improve the mechanical properties of starch-based materials: plasticization and natural fibers reinforcement

Biodegradable polymers are starting to be introduced as raw materials in the food-packaging market. Nevertheless, their price is very high. Starch, a fully biodegradable and bioderived polymer is a very interesting alternative due to its very low price. However, the use of starch as the polymer matrix for the production of rigid food packaging, such as trays, is limited due to its poor mechanical properties, high hidrophilicity and high density. This work presents two strategies to overcome the poor mechanical properties of starch. First, the plasticization of starch with several amounts of glycerol to produce thermoplastic starch (TPS) and second, the production of biocomposites by reinforcing TPS with promising fibers, such as barley straw and grape waste. The mechanical properties obtained are compared with the values predicted by models used in the field of composites; law of mixtures, Kerner-Nielsen and Halpin-Tsai. To evaluate if the materials developed are suitable for the production of food-packaging trays, the TPS-based materials with better mechanical properties were compared with commercial grades of oil-based polymers, polypropylene (PP) and polyethylene-terphthalate (PET), and a biodegradable polymer, polylactic acid (PLA).

Escape depth of secondary electrons from electron-irradiated polymers

Measurements on polymers (Teflon FEP and Mylar) have shown that the secondary electron emission from uncharged surfaces exceeds that from surfaces containing a positive surface charge. The reduced emission of charged surfaces is due to recombination between electrons undergoing emission and trapped holes within the charged layer. During the experiments the surface of the material was kept at a negative potential to assure that all secondary electrons reaching the surface from within the material are actually emitted. An analysis of the results yielded the maximum escape depth of the secondary electrons, and showed that the ratio of the maximum escape depth of the secondaries from Mylar to the maximum escape depth from Teflon is almost the same as the ratio of the corresponding second crossover energies of this polymers.

The effects of fiber inclusion on pet food sensory characteristics and palatability

The objectives of this study were to determine (a) the influence of fiber on the sensory characteristics of dry dog foods; (b) differences of coated and uncoated kibbles for aroma and flavor characteristics; (c) palatability of these dry dog foods; and (d) potential associations between palatability and sensory attributes. A total of eight fiber treatments were manufactured: a control (no fiber addition), guava fiber (3%, 6%, and 12%), sugar cane fiber (9%; large and small particle size), and wheat bran fiber (32%; large and small particle size). The results indicated significant effects of fibers on both flavor and texture properties of the samples. Bitter taste and iron and stale aftertaste were examples of flavor attributes that differed with treatment, with highest intensity observed for 12% guava fiber and small particle size sugar cane fiber treatments. Fracturability and initial crispness attributes were lowest for the sugar cane fiber treatments. Flavor of all treatments changed after coating with a palatant, increasing in toasted, brothy, and grainy attributes. The coating also had a masking effect on aroma attributes such as stale, flavor attributes such as iron and bitter taste, and appearance attributes such as porosity. Palatability testing results indicated that the control treatment was preferred over the sugar cane or the wheat bran treatment. The treatment with large sugarcane fiber particles was preferred over the treatment with small particles, while both of the wheat bran treatments were eaten at a similar level. Descriptive sensory analysis data, especially textural attributes, were useful in pinpointing the underlying characteristics and were considered to be reasons that may influence palatability of dog foods manufactured with inclusion of different fibers.

Jato de plasma frio em pressão atmosférica para tratamento de materiais e esterilização

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Improvement of the alcohol dehydrogenase from baker's yeast using polymers and salts for alcohol determinations in beverages

An alcohol dehydrogenase (ADH) was purified from dry baker’s yeast. This is a key enzyme of the primary short-chain alcohol metabolism in many organisms. In the present study, the obtained enzymatic preparation of baker’s yeast, containing 2.7 U/mg of ADH, was used in the reactions. The purified extract of the ADH obtained from Fermix commercial dry yeast, presented the highest activity and purification factor when ammonium sulfate was added in the precipitation of protein, in the range 35-60% (w/v). The enzymatic preparation was maintained for 2 months in the lyophilized form at 4ºC (retention of 96.2% of activity) in the presence of 1 mmol/L of sodium azide, and it maintained 47% of activity for 30 days at 30°C in the presence of 15% PEG. The assays of ethanol (detection range 5 mM -150 mM or 2.3 x 10-4 – 6.91 x 10-3g/L) in different samples in alcoholic beverages, presented a maximum deviation of only 2.1%. Assays of recovery of the substrate (99.25%) added in the wine showed that the methodology is viable for this sample type. The standard curve and the analytic curve of this method meet the conditions of precision, sensitivity, simplicity, and low cost, required for a useable analytical method.

A influência da idade na percepção de dificuldade de abertura de embalagens PET para refrigerantes

Nowadays, there is an increasing demand for subjective aspects of the interface between human beings and the products and systems that surround them, whether in the workplace or at home. This study addresses the association of age and the perception of difficulty during a simulation of opening process PET bottles for soft drinks. During the activities, the subjects exerted their maximum torque forces, trying to open five different models of these packages, and then they assigned scores for perception in a scale. The results indicate that for some models, there were differences between levels of perceived difficulty between age groups.

Gamma-ray dosimetric properties of conjugated polymers in solution

The effect of gamma radiation on poly{[2,5-bis(3-(N,N-diethylamino)-1-oxapropyl)-1,4-phenylene]-alt-1,4- phenylene} (PPP); poly{[2,5-bis(3-(N,N-diethylammonium bromide)-1-oxapropyl)-1,4-phenylene]-alt-1,4-phenylene} (PPP-Br); and the polymerized dye poly-1-ethyl-2-[3-(1-ethyl-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)-1-propenyl]- 3,3-dimethyl-3H-indolium perchlorate (Poly-CyC) has been investigated. The stability and response of poly [2-methoxy- 5-(2'- ethyl-hexyloxy)-p-phenylenevinylene] (MEH-PPV) in mixed solutions have also been explored. To this end, samples with concentrations ranging from 0.005 to 0.500 mg/mL were irradiated with a 60Co gamma-ray source at room temperature, using doses up to 1 kGy, and the response was analyzed by UV-Vis spectroscopy. The obtained results reinforce the previously proposed mechanism and suggest that the effect depends on specific structural characteristics of the main chain of the polymers. Moreover, the polymerized dyes display interesting dosimetric properties. Additionally, it has been noted that, contrary to what happens in other solvents, MEH-PPV is degraded in bromoform solution. Protective effects have also been observed for bromoform+toluene mixtures (1:1 vol/vol) and solutions containing molecular dyes. - See more at: http://www.eurekaselect.com/117251/article#sthash.gHFnYvJk.dpuf

Quality and safety of pet treats: assessment of the microbial safety and quality of pet treats

The aim of this study was to evaluate the hygienic and sanitary conditions of pettreats from an export industry. The occurrence of Salmonella, enumerated sulfite-reducing Clostridium (SRC), coagulase-positive Staphylococcus (CPS) and total(TC) and thermotolerant coliforms (TTC) was studied. Of the 108 samples ana-lyzed, 22 were contaminated by some microorganism. TC were detected at twosamples (3.5 × 101and 4.5 × 101colony-forming units [cfu]/g), SRC in 19 samples(1.0 × 101to 1.3 × 105cfu/g) and Salmonella spp. at only one sample; CPS andTTC were not detected. These findings indicate the microbiological safety of mostitems, except for a mix of dried bovine offal, with 1.3 × 105cfu/g of SRC, and onemix of dehydrated bovine viscera contaminated with Salmonella. The current pro-duction processes and the food safety management system are adequate to guar-antee the production of microbiologically safe foods, but that some improvementscan still be made with regard to cleaning and disinfection and hygiene training.

Análise do processo de construção de um ambiente constituído por garrafas pet

O desenvolvimento tecnológico crescente associado a profundas mudanças no modo de vida contemporâneo tem gerado volumes de rejeitos cada vez maiores. Um desses rejeitos são as garrafas feitas de PET. Essas garrafas podem ser aproveitadas para construções de ambientes em substituição dos tijolos. O objetivo deste trabalho foi estudar os aspectos necessários para a realização das obras de construção de um ambiente com materiais recicláveis analisando tipos, quantidades e custos dos materiais de construção e mão-de-obra. Além disso, criou-se estratégias para a arrecadação de garrafas pet, métodos de preenchimento das mesmas e mecanismos de divulgação do projeto intitulado ?Projeto Casa PET?. O estudo comprovou que a garrafa pet pode substituir o tijolo, que um dos materiais adequados para preenchê-las é o solo-cimento e que este tipo de construção tem despertado o interesse de pessoas de diversos locais do Brasil e até mesmo de outros países. Em futuros trabalhos, pretende-se comprovar que o ambiente é uma alternativa viável tanto do ponto de vista econômico e ambiental.

Membranas de biocelulose como substrato para o crescimento de nanofios de ZnO: síntese e aplicação

Pós-graduação em Química - IQ

Intervenção do PET-Saúde para a melhoria do conhecimento sobre doenças sexualmente transmissíveis e gravidez em adolescentes que frequentam a rede pública de ensino

A transmissão de Doenças Sexualmente Transmissíveis (DSTs) tem aumentado significativamente nos últimos anos entre os adolescentes, como apresentam os dados do Boletim Epidemiológico de AIDS publicado pelo Ministério da Saúde, juntamente com o aumento do número de adolescentes grávidas. Dessa forma, o projeto de extensão PET - Saúde objetiva transmitir um conhecimento prevencionista aos jovens vulneráveis a essa situação, trabalhando com estudantes do ciclo II do ensino fundamental dos colégios municipais de Nova Europa. Os alunos que participaram da atividade responderam voluntariamente um questionário antes e após a atividade, que avaliava qualitativamente o conhecimento que possuíam acerca do tema DSTs e gravidez na adolescência. Através da análise desses questionários, foi possível perceber que os jovens possuíam conhecimento sobre o uso de preservativo para a prevenção de DSTs e gravidez (86,9% e 82,8%), mas que o mesmo não se aplicava quanto ao conhecimento de sintomas de DSTs (66,8%), que foi aprimorado após a atividade (80%). Além disso, as meninas apresentaram conhecimento acerca de outros métodos contraceptivos diferentes do preservativo e importância da vacina contra o HPV, provavelmente pelo fato dos meninos lidarem com a vida sexual de uma forma diferente. Apesar de conhecimento prévio sobre o assunto, ações educativas contínuas podem aumentar o conhecimento dos jovens sobre DSTs e gravidez.