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| Registros recuperados: 21 | |
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| SIMBINE,Emelda Orlando; RODRIGUES,Larissa da Cunha; LAPA-GUIMARÃES,Judite; KAMIMURA,Eliana Setsuko; CORASSIN,Carlos Humberto; OLIVEIRA,Carlos Augusto Fernandes de. |
| Abstract Silver nanoparticles (AgNPs) are antimicrobial agents that have a wide spectrum of action, including against pathogenic bacteria and spoilage fungi. However, their mechanism of action is not completely clarified. Nowadays, scientific interest on biological synthesis of AgNPs is growing, with emphasis in their extracellular biosynthesis by microbial cells, as it is the most reliable and ecologically correct method for production, yielding no toxic residues. AgNPs may be incorporated to biodegradable and non-biodegradable polymers for the production of food packages with antimicrobial properties, leading to greater safety and longer shelf life. However, it is important to carry out migration tests for new food packages incorporated with AgNPs, based... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Silver nanoparticles; Antimicrobial activity; Food packaging; Polymers. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612019000400793 |
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| Farias,Fabiane Oliveira; Jasko,Ariana Crasnhak; Colman,Tiago André Denck; Pinheiro,Luís Antônio; Schnitzler,Egon; Barana,Ana Cláudia; Demiate,Ivo Mottin. |
| The main objective of this study was to characterise the cassava bagasse and to evaluate its addition in composites. Two cassava bagasse samples were characterised using physicochemical, thermal and microscopic techniques, and by obtaining their spectra in the mid-infrared region and analysing them by using x-ray diffraction. Utilising sorption isotherms, it was possible to establish the acceptable conditions of temperature and relative humidity for the storage of the cassava bagasse. The incorporation of cassava bagasse in a low-density polyethylene (LDP) matrix was positive, increasing the elasticity modulus values from 131.90 for LDP to 186.2 for 70% LDP with 30% SP bagasse. These results were encouraging because cassava bagasse could serve as a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Manihot esculenta Crantz; Residue; Polymers. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132014000600821 |
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| Baral, N; Davies, Peter; Baley, C; Bigourdan, Benoit. |
| This paper presents a study of the delamination resistance Of unidirectional carbon fibre reinforced epoxy composites manufactured from prepreg for racing yacht mast applications. Fibre modulus has been varied from 290 to 640 GPa. Two manufacturing methods, oven cure under vacuum and autoclave, were used to produce samples. Results show that delamination resistance tinder mode I and mixed mode loading decreases as fibre modulus increases. The manufacturing route affects G, values by modifying interlaminar layer geometry but does not change the trend of lower toughness with increasing fibre modulus. For the pitch composites crack propagation is observed within the fibres, in addition to more usual matrix and interface cracking. For the very high modulus... |
| Tipo: Text |
Palavras-chave: Mixed mode; Fracture toughness; Polymers; Carbon fibres; Delamination. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3772.pdf |
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| Battersby, N; Stewart, D; Sharma, A. |
| Chemical additives are used extensively in the offshore oil industry. For secondary oil recovery, the biopolymer xanthan has been recommended as a viscosifying agent but its use may provoke microbial problems. The effect of adding xanthan to marine sediments on the growth and metabolic activity of sulphate-reducing bacteria (SRB) was studied. In all instances, its addition resulted in an increasing in SRB numbers of up to 250-fold. This was accompanied by a marked increase in the electron transport activity of the sediments when these were incubated under either aerobic or anaerobic conditions. The products formed as a result of the biodegradation of the polymer by indigenous heterotrophic bacteria in these sediments appear to have acted as suitable... |
| Tipo: Text |
Palavras-chave: Bacteria; Growth; Additives; Pollution effects; Oil recovery; Biodegradation; Polymers; Sediment pollution; Sulfate reduction. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1015.pdf |
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| OLIVEIRA, A. P. V.. |
| A produção de pescado, especificamente, tilápia e camarão geram um enorme montante de resíduo com potencial para a agregação de valor. Uma alternativa para o aproveitamento integral do pescado é a extração de moléculas com características químicas e físicas adequadas para a formulação de microcápsulas e hidrogéis como base para o desenvolvimento de novos produtos inclusive na área de alimentos e biomédica. Dentre essas moléculas, o colágeno é a principal proteína estrutural no corpo, tem como função promover elasticidade e sustentação a pele, ossos, cartilagens e tendões. Glicosaminoglicanos são encontrados nos ossos, cartilagens e tecidos conjuntivos de vertebrados, atualmente usado no tratamento de osteoartrose. Diante disso, o objetivo do presente... |
| Tipo: Teses |
Palavras-chave: Agente Reticulante; Polymers; Gels. |
| Ano: 2018 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1103411 |
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| Toledo,Lucas de Alcântara Sica de; Bavato,Maíra Isabeli; Rosseto,Hélen Cássia; Cortesi,Rita; Bruschi,Marcos Luciano. |
| abstract This study investigated the development and characterized the physicochemical properties of films obtained from by-products (BP) from the preparation of propolis extracts. Films were produced in the presence and absence of a polymeric adjuvant (gelatin or ethylcellulose) and propylene glycol by a solvent casting method. Density, surface topography by scanning electron microscopy, mechanical properties (folding endurance, tensile strength and percentage elongation), water vapour permeability (WVP), moisture uptake capacity, thermogravimetry, differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR) were determined. The films were a transparent, light greenish-yellow colour, with a uniform surface, and were flexible and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Propolis/byproducts; Propolis/use of waste material/films development; Films/propolis byproducts/physicochemical properties; Polymers; Ethylcellulose; Gelatin. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502015000400847 |
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| NASCIMENTO, J. A. de A.; SANTOS, A, F. dos; SILVA, I. D. L.; FALCÃO, E. H. L.; BRITTO, D. de; VINHAS, G. M.. |
| Biodegradable polymeric blends have been widely studied due to their potential of reducing pollution caused by non-biodegradable materials. The research described here describes a polymer blend that benefits both from the abundance of arrowroot starch (AS) and the good mechanical properties of poly(vinyl alcohol) (PVA). Glycerol (GLY) was used in different proportions as a plasticizer. The addition of GLY improved the mechanical properties of the blends, increasing the elongation at break up to 667%. On the other hand, the GLY addition adversely affected other properties, increasing the water vapor permeability (WVP), solubility and hydrophilic characteristics and reducing the thermal stability and the crystallinity index. The AS/PVA blend without GLY... |
| Tipo: Artigo de periódico |
Palavras-chave: Amido de araruta; Filme de embalagem; Álcool polivinílico; Mistura de polímeros; Polissacarídeo; Arrowroot starch; Packaging films; Polymers; Polysaccharides. |
| Ano: 2021 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1147276 |
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| Registros recuperados: 21 | |
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