Surfactants
Mostrando 25-36 de 396 artigos, teses e dissertações.
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25. Soil Biodegradation of PLA/CNW Nanocomposites Modified with Ethylene Oxide Derivatives
Due to its ester bonds, poly(lactic acid) (PLA) undergoes biodegradation in humid environments, attracting market attention. The goal of this work was to observe the biodegradation in garden soil of PLA nanocomposites with neat (PLA/CNW) and surfactant modified cellulose nanowhiskers (PLA/CNW/S). Three types of surfactants were tested: poly(ethylene glycol)
Mat. Res.. Publicado em: 01/03/2018
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26. Experimental Multi-scale analysis of Carbon/Epoxy Composites Nano-Reinforced by Carbon Nanotubes/Multi-layer Graphene
Nano-size structures, nanotubes/multi-layer graphene (CNT/MLG), were dispersed into epoxy system by a combination of sonication and high shear mixing. To avoid CNT/MLG agglomeration, a non-covalent functionalization were performed using surfactants, CO890 - Polyoxyethylene (40) nonylphenyl ether and SDBS - sodium dodecyl benzene sulfonate. Raman spectroscopy
Mat. Res.. Publicado em: 22/01/2018
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27. Effect of Acetonitrile and N,N-Dimethylformamide on the Formation of Poly(ethylene oxide)-Sodium Alkyl Sulfate Aggregates
The effects of low contents of acetonitrile (AN) or N,N-dimethylformamide (DMF) on the aggregation of sodium alkyl sulfate surfactants, in the absence and presence of poly(ethylene oxide) (PEO), were investigated using conductivity and isothermal titration calorimetry. The cosolvents slightly changed the critical micellar concentrations and did not alter the
J. Braz. Chem. Soc.. Publicado em: 2018-01
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28. Molecular Dynamics Simulations of Cetyltrimethylammonium Bromide (CTAB) Micelles and their Interactions with a Gold Surface in Aqueous Solution
Surfactants are molecular structures with remarkable physicochemical properties and applications. Most of their characteristics are due to their ability to promote aggregation and interactions with different interfaces. The scarcity of theoretical studies dedicated to evaluating the forces involved in these interactions prompted us to propose other models ca
J. Braz. Chem. Soc.. Publicado em: 2018-01
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29. Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region
Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of
Braz J Med Biol Res. Publicado em: 11/12/2017
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30. Pterodon pubescens oil nanoemulsions: physiochemical and microbiological characterization and in vivo anti-inflammatory efficacy studies
Abstract Pterodon pubescens (Benth.) Benth., Fabaceae, fruits have been investigated for their anti-inflammatory and antinociceptive activities, and have demonstrated effectiveness in inflammatory conditions. A physiochemical and microbiological stability study was conducted to investigate two nanoemulsion-based delivery systems of two different hydrophilic
Rev. bras. farmacogn.. Publicado em: 2017-06
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31. Utilization of dynamic light scattering to evaluate Pterodon emarginatus oleoresin-based nanoemulsion formation by non-heating and solvent-free method
Abstract Pterodon emarginatus Vogel, Fabaceae, is a great source of bioactive compounds. The most known and studied herbal derivative from this species is an ambar-colored oleoresin that contains vouacapane diterpenes and volatile terpenoids, such as β-caryophyllene. Some recent papers aimed to generate nanoemulsions using this oleoresin for biological appl
Rev. bras. farmacogn.. Publicado em: 2017-06
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32. Novos surfactantes alquil poliglicosídicos à base de amilose extraída da batata inglesa (Solanum tuberosum L.)
Alkyl polyglycosides (APGs) are new biodegradable surfactants, non-toxic, synthesized from abundant renewable sources, potentially more appropriate than anionic surfactants. A range of glycosides denoted APG-Cy was synthesized by the Köenig-Knorr reaction using C10, C16 and C18 alcohols and derived from the degradation of amylose from English potato. The mo
Quím. Nova. Publicado em: 2017-04
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33. Binary systems of Brij® surfactants with Pluronic® F127 as griseofulvin carrier
The binary mixtures of Brij® surfactant and Pluronic® F127 were studied as carriers of griseofulvin. The F127 systems and Brij® 78 (C18H37E20), Brij® 98 (C18H35E20) and Brij® 700 (C18H37E100) were prepared in the proportions 10/90, 30/70, 50/50 and 70/30, respectively. The characterizations were carried out by tube inversion, rheology, particle size, an
Quím. Nova. Publicado em: 2017-04
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34. Effect of Capping Agent on the Morphology, Size and Optical Properties of In2O3 Nanoparticles
The Indium Oxide (In2O3) nanoparticles were synthesized through Acacia gum mediated method with the surfactants CTAB (Cetyl Trimethyl Ammonium Bromide) and SDBS (Sodium Docecyl Benzene Sulfonate). The characterization of the synthesized In2O3 nanoparticles was carried out by XRD, FTIR, RAMAN, TEM, SEM, EDAX, UV-Vis and PL techniques. TG-DTA analysis was perf
Mat. Res.. Publicado em: 09/01/2017
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35. EFFECTS OF NANOPARTICLES AND SURFACTANT CHARGE GROUPS ON THE PROPERTIES OF VES GEL
Abstract Application of viscoelastic surfactant (VES) fluids in hydraulic fracturing is still in the development stage, though shear thinning behavior and water solubility are the two important characteristics behind increasing interest in their use in fracturing jobs. Effects of ionic characteristics and the concentration of different surfactants on the rhe
Braz. J. Chem. Eng.. Publicado em: 2017-01
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36. Purification and characterization of extracellular α-amylase from a thermophilic Anoxybacillus thermarum A4 strain
ABSTRACT α-Amylase from Anoxybacillus thermarum A4 was purified using ammonium sulphate precipitation and Sephadex G-100 gel filtration chromatography, with 29.8-fold purification and 74.6% yield. A4 amylase showed best performance for soluble potato starch hydrolysis at 70 °C and pH 5.5-10.5. A4 amylase was extremely stable at +4 °C, and the enzyme retai
Braz. arch. biol. technol.. Publicado em: 01/12/2016