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The aim of this study was to evaluate the effects of iron (Fe)/SDS and gold (Au) nanoparticles on growth and biosurfactant production of Pseudomonas aeruginosa PBCC5. The concentrations of the nanoparticles used were 1, 500 and 1000 mg/l. In this research, the surface tension of biosurfactant, dry weight of biosurfactant and biomass, emulsification indexes (E24) were measured and transmission electron microscopy analysis was used to monitor the nanoparticles. The test results showed that the effect of nanoparticles on the bacterial growth and biosurfactant production varied corresponding to the type and concentration of nanoparticles. Fe/SDS nanoparticles showed no bacterial toxicity when the concentration of nanoparticles was 1 mg/ml and increased the growth and biosurfactant production, 23.21 and 20.73%, respectively. While at higher concentrations (500, 1000 mg/l), the nanoparticles suppressed bacterial growth as well as biosurfactant production. Similarly, Au nanoparticles had no bacterial toxicity and also increased bacterial growth and biosurfactant production. The surface tensions of all samples decreased from 72 of distiled water to 32–35 mN/m.Inspec keywords: nanoparticles, iron, gold, nanofabrication, nanomedicine, surfactants, biomedical materials, surface tension, renewable materials, transmission electron microscopy, microorganismsOther keywords: Au nanoparticles, P. aeruginosa bacterial growth, biosurfactant production, Pseudomonas aeruginosa PBCC5, surface tension, biomass, emulsification indexes, dry weight, transmission electron microscopy, Fe‐SDS nanoparticles, distiled water, Fe, Au 相似文献
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Sh. Rasekh M. A. Torres G. Constantinescu M. A. Madre J. C. Diez A. Sotelo 《Journal of Materials Science: Materials in Electronics》2013,24(7):2309-2314
Ca3Co4?xCuxO9 polycrystalline thermoelectric ceramics with small amounts of Cu have been synthesized by the classical solid state method. X-ray diffraction data have shown that all the Cu has been incorporated into the Ca3Co4O9 structure and no Cu-containing secondary phases have been produced. Apparent density measurements have shown that all samples are very similar, with densities around 75 % of the theoretical one. Electrical resistivity decreases when Cu content increases until x = 0.03 while Seebeck coefficient remains practically constant for all samples. The improvement in resistivity leads to higher power factor values than the obtained for the undoped samples. 相似文献
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J. C. Diez G. Constantinescu S. Rasekh L. C. Estepa M. A. Madre A. Sotelo 《Journal of Superconductivity and Novel Magnetism》2013,26(4):895-900
It is well know that H2O and CO2 (both present in the atmosphere) can react chemically with BSCCO superconductors, especially with the alkaline–earth cations, producing chemical degradation and reducing their performances. In this work, Bi-2212 highly textured rods were grown from the melt through a laser floating zone melting technique. In order to determine the influence of H2O and CO2 on these bulk textured samples, they were immersed in distilled water and in CO2 saturated water. The evolution of the electrical and mechanical properties of these rods was determined as a function of the immersion time in both media and compared with their initial properties. It has been found that performance degradation was higher in distilled water than in CO2 saturated one. Nevertheless, in any case, the degradation has been found to be not very important. 相似文献
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J.C. Diez M.A. Torres Sh. Rasekh G. Constantinescu M.A. Madre A. Sotelo 《Ceramics International》2013
Ca3Co4−xCrxO9 polycristalline thermoelectric ceramics with small amounts of Cr have been synthesized by the classical solid state method. Microstructural characterizations have shown that all the Cr has been incorporated into the Ca3Co4O9 structure and no Cr-containing secondary phases have been produced for Cr contents≤0.05. Apparent density measurements have shown that all samples are very similar, with densities around 75% of the theoretical one. Electrical resistivity decreases and Seebeck coefficient slightly raises when Cr content increases until 0.05 Cr addition. The improvement in both parameters leads to higher power factor values than the usually obtained by conventional solid state routes. 相似文献
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A. Sotelo G. Constantinescu Sh. Rasekh M.A. Torres J.C. Diez M.A. Madre 《Journal of the European Ceramic Society》2012,32(10):2415-2422
Two solution synthetic methods, sol–gel and a polymeric route, have been studied in order to obtain Ca3Co4O9 misfit compounds with improved thermoelectric properties, compared to the classical solid state reaction. A comparison among the final products obtained by these different methods has been performed using DTA, TGA, FTIR, X-ray diffraction, scanning electron microscopy, and thermoelectric characterizations. All the samples obtained by solution synthesis show a very significative reduction on the secondary phases content. As a consequence, an important decrease on the electrical resistivity values is produced, compared to the solid state prepared samples, leading to a relatively important power factor raise. 相似文献
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A. Sotelo S. Rasekh M. A. Madre J. C. Diez 《Journal of Superconductivity and Novel Magnetism》2011,24(1-2):19-25
Several synthetic methods, solid-state, sol-gel and polymer solution methods, have been used to prepare prereacted precursors, as well as a vitreous material obtained by melt quenching. The influence of the starting powder characteristics on the phase formation, microstructure, T c and J c of Bi-2212 textured rods prepared by directional crystallization from the melt has been analyzed. In all the cases, high transport critical current values (higher than 3000 A/cm2 at 77 K) have been obtained, independently of the precursor type. Samples obtained by the polymer route show improved T c values, associated to a lower oxygen content. 相似文献
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Dai Yue Rasekh Maryam Eslami Mirfarshbafan Seyed Hadi Liew Harrison Gallyas-Sanhueza Alexandra Dunn James Madhow Upamanyu Studer Christoph Nikolić Borivoje 《Journal of Signal Processing Systems》2022,94(10):989-1003
Journal of Signal Processing Systems - This paper presents an algorithm-adaptable, scalable, and platform-portable generator for massive multiple-input multiple-output (MIMO) baseband processing... 相似文献