Polymeric
Mostrando 13-24 de 1320 artigos, teses e dissertações.
-
13. DURABILITY OF HDPE GEOMEMBRANES: AN OVERVIEW
The polymer demand for geotechnical applications has been growing. The geomembrane is a geosynthetic, manufactured, polymeric product and is often specified in environmental projects. Geomembranes started to be used in the 1930s but became more widespread in the 1940s. In the 1970s, geomembranes began to be specified for landfills. Over the past forty years,
Quím. Nova. Publicado em: 2020-05
-
14. RAMAN STUDIES OF BIS(PHENYLTERPYRAZINE)IRON(II) AND SUPRAMOLECULAR SPECIES WITH PENTACYANIDOFERRATE(II) IONS
The chemistry and spectroscopy of the iron(II) phenylterpyrazine complex, [Fe(phtpz)2]2+, were investigated in comparison with the analogous phenylterpyridine species, Fe(phtpy)2]2+, and the results indicated a strong electronic delocalization on the Fe(II) terimine chromophore encompassing the lateral pyrazyl groups. The delocalized nature of the molecular
Quím. Nova. Publicado em: 05/12/2019
-
15. Physical and mechanical properties of low, ultralow and no cement refractory castables containing MgO nanoparticles developed in situ by means of polymeric resins
Resumo A introdução de nanopartículas de MgO desenvolvidas in situ na matriz de concretos refratários de baixo teor de cimento, ultrabaixo e sem cimento foi feita por meio de uma resina polimérica aquosa de baixa viscosidade, produzida pelo método Pechini. A adição da resina líquida aos concretos desempenhou dois papéis: primeiro serviu como fornec
Cerâmica. Publicado em: 14/11/2019
-
16. Preparation of Syntactic Foams made from Green Polyethylene and Glass Microspheres: Morphological and Mechanical Characterization
Polymeric syntactic foams are composites made from the mixture of Hollow Glass Microspheres (HGM) and polymer matrices. One of their main characteristics is their low density and the production of these composites using a matrix derived from renewable sources potentiates their development without neglecting sustainability. In this paper , the properties of H
Mat. Res.. Publicado em: 11/11/2019
-
17. In vitro evaluation of PVA gels loaded with Copaiba Oil and Duotrill®
Abstract Enrofloxacin can be slowly delivered through polymeric systems and the addition of oil could increase the polymeric gels hydrophobicity and help the continuous release. The present work intended to develop and characterize microstructurally (XRD and FTIR) and in vitro (swelling and antimicrobial tests) the PVA hydrogels loaded with copaiba oil and D
Polímeros. Publicado em: 04/11/2019
-
18. Halogen Determination in Polymeric Waste of Electrical and Electronic Equipment: Overcoming Limitations in Sample Preparation
Sample preparation of polymers for halogen determination requires special attention because they are difficult to bring into solution and due to the risk of analyte losses when using acid digestion. A method using microwave-induced combustion (MIC) was optimized for accurate determination of halogens in polymeric parts obtained in waste of electrical and ele
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
19. Nanoparticles of Fe2O3 and Co3O4 as Efficient Electrocatalysts for Oxygen Reduction Reaction in Acid Medium
This paper presents a comparative study about the oxygen reduction reaction (ORR) catalyzed by nanoparticles of Fe2O3 and Co3O4 applied on the surface of glassy carbon electrodes (GCE). The nanoparticles were synthesized using the modified polymeric precursor method (Pechini). These two nanomaterials were characterized by Fourier transform infrared spectrosc
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
20. Magneto-Responsive Hydrogels: Preparation, Characterization, Biotechnological and Environmental Applications
Hydrogels are hydrophilic three-dimensional networks able to hold large amount of water and hydrophilic molecules. Magneto-responsive hydrogels comprise of magnetic nanoparticles dispersed in polymeric networks that can be manipulated under external magnetic field. This review aims at (i) giving a brief overview on the evolution of hydrogels until the design
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
-
21. EFEITO DO PH, ESPÉCIE E CONCENTRAÇÃO IÔNICA NA ABSORÇÃO DE ÁGUA DE HIDROGÉIS BIONANOCOMPÓSITOS CONSTITUÍDOS DE CMC/PAAM/LAPONITA RDS
The objective of this paper was to study the effect of pH, concentration and ionic species on the water absorption of the bionanocomposite hydrogels based on carboxymethylcellulose polysaccharide and laponite nanoclay. Bionanocomposite hydrogels were obtained via free radical polymerization. It was possible to observe that the swelling degree (Q) and kinetic
Quím. Nova. Publicado em: 21/10/2019
-
22. Crosslinking starch/oat hull mixtures for use in composites with PLA
Abstract Modification of composite components has been proposed as a tool to improve their functional properties. The present work studied crosslinking of a starch/oat hull mixture by reactive extrusion with sodium trimetaphosphate (STMP), for application in composites with polylactic acid (PLA). The treated mixture was characterized regarding degree of subs
Polímeros. Publicado em: 10/10/2019
-
23. EFFECT OF ALUMINUM SULFATE AND CATIONIC POLYMER ADDITION IN THE MIXED LIQUOR OF A SUBMERGED MEMBRANE BIOREACTOR (SMBR): SLUDGE CHARACTERISTICS AND ORTHOPHOSPHATE REMOVAL IN BATCH EXPERIMENTS
Abstract Submerged Membranes Bioreactors (SMBR) are an established technology for wastewater treatment for water recovery and reuse. However, its routine application is still compromised by the high energy consumption to overcome the fouling effect. This study evaluated the effect of aluminum sulfate and cationic polymer in the orthophosphate removal and slu
Braz. J. Chem. Eng.. Publicado em: 30/09/2019
-
24. Avaliação de amidos modificados empregados na mineração para aplicação em fluidos de perfuração de poços de petróleo
RESUMO Amidos e seus derivados são utilizados em praticamente todos os setores industriais. Na indústria petrolífera podem ser empregados como aditivos controladores de filtrado, os quais controlam eficazmente a perda de fluido para a formação rochosa adjacente. O presente trabalho teve como objetivo avaliar o uso de amidos, de mandioca e de milho, util
Matéria (Rio J.). Publicado em: 16/09/2019