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991.
Removal of the drug Gemfibrozil (GEM), as a target molecule, from aqueous media by using a carrier mediated transport in supported liquid membrane (SLM) and Stagnant Sandwich LM (SSwLM) systems has been investigated. Optimal chemical conditions to use in the transport tests were determined by means of solubility and liquid–liquid extraction tests. The results showed that the best LM phase to realize stable LM systems was tributylphosphate (TBP) 30% (v/v) in n-decane. Transport tests by using the “traditional” SLM system showed an average flux JAV(0–CTT) of 0.421 mmol h−1 m−2 and a system stability of 1410 min. Three different microfiltration membranes, GH-Polypro, FP-Vericel and Supor 200, made of polypropylene, polyvinylidene fluoride and polyethersulphone polymers, respectively, were used to assemble the SSwLM. Contact angle and adsorption measurements evidenced hydrophilic/lypophilic character of the supports. The best results in terms of average flux (0.873 mmol h−1 m−2), permeability coefficient (21.88 L h−1 m−2) and stability (7170 min ≈120 h) were obtained by using the SSwLM made with the Supor 200 support. The overall results showed that the SSwLM made with this type of support achieves both high flux and high stability compared to the SLM. Thus SSwLMs seems very interesting to employ transport in LM for removing molecular species (e.g. drugs) from aqueous solutions. 相似文献
992.
Marcella Bini Pietro Galinetto Stefania Ferrari Vincenzo Massarotti 《Journal of solid state chemistry》2009,182(7):1972-1981
Different solid state and sol-gel preparations of undoped and Mn substituted cathode material LiFePO4 are investigated. Li3PO4, Fe2P2O7 and Li4P2O7 are detected and quantified by XRPD only in solid state synthesis. In addition, micro-Raman spectra reveal low amount of different iron oxides clusters. EPR data, combined with the results of magnetization measurements, evidence signals from Fe3+ ions in maghemite nanoclusters, and in Li3Fe2(PO4)3. The sol-gel synthesis, showing the lowest amount of impurity phases, seems the most suitable to obtain a promising cathode material. The structural refinement gives new insights into the cation distribution of the Mn doped triphylite structure: (i) about 85% of Mn2+ ions substitutes Fe2+, the remaining 15% being located on the Li site, thus suggesting a structural disorder also confirmed by EPR and micro-Raman results; (ii) Mn ions on the Li site are responsible for the observed slight cell volume expansion. 相似文献
993.
Pietro Galinetto Maria Cristina Mozzati Marco Simone Grandi Marcella Bini Doretta Capsoni Stefania Ferrari Vincenzo Massarotti 《Journal of Raman spectroscopy : JRS》2010,41(10):1276-1282
Thermal stability and phase homogeneity of the triphylite LiFePO4 compound were investigated by means of Raman spectroscopy. A detailed check of phase homogeneity of undoped samples obtained from different preparation routes—hydrothermal, sol–gel, and solid state synthesis—and Mn‐doped compounds from solid‐state synthesis was performed by means of a mapping of the Raman spectra. The triphylite compositional and structural properties were carefully investigated also with the help of structural refinements and magnetic techniques, which also allowed us to reveal and identify the impurity phases formed together with the olivine LiFePO4. The effect of laser irradiation on the triphylite thermal stability was thoroughly investigated and related to the synthesis route, to the doping, and to the sample homogeneity. The thermal stability of iron oxides, present both as synthesis products and as consequence of the irradiation itself, was also analyzed following the magnetite→maghemite→hematite phase transformation. All the experimental observations concur in indicating that the effectiveness of the laser heating on these compounds mainly depends on grain size and the degree of order of the olivine structure, the highest thermal stability being displayed in the case of the nonhomogenous undoped samples obtained from solid‐state preparation, which show a highly ordered triphylite phase. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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995.
F. Amorini V. Sipala G. Cardella L. Auditore C. Boiano B. Carbone A. Di Pietro G. Fallica P. Figuera P. Finocchiaro L. Grassi E. La Guidara P. Guazzoni I. Lombardo D. Loria A. Pappalardo A. Piazza S. Pirrone N. Randazzo F. Rizzo L. Zetta 《Nuclear Physics B - Proceedings Supplements》2009,173(1):194-197
996.
Gianfranco Carotenuto Cornelia L. Hison Filomena Capezzuto Mariano Palomba Pietro Perlo Pellegrino Conte 《Journal of nanoparticle research》2009,11(7):1729-1738
An effective method of preparation of bismuth nanopowders by thermal decomposition of bismuth dodecyl-mercaptide Bi(SC12H25)3 and preliminary results on their thermoelectric properties are reported. The thermolysis process leads to Bi nanoparticles
due to the efficient capping agent effect of the dodecyl-disulfide by-product, which strongly bonds the surface of the Bi
clusters, preventing their aggregation and significantly reducing their growth rate. The structure and morphology of the thermolysis
products were investigated by differential scanning calorimetry, thermogravimetry, X-ray diffractometry, 1H nuclear magnetic resonance spectroscopy, scanning electron microscopy, and energy dispersive spectroscopy. It has been shown
that the prepared Bi nanopowder consists of spherical shape nanoparticles, with the average diameter depending on the thermolysis
temperature. The first results on the thermoelectric characterization of the prepared Bi nanopowders reveal a peculiar behavior
characterized by a semimetal–semiconductor transition, and a significant increase in the Seebeck coefficient when compared
to bulk Bi in the case of the lowest grain size (170 nm). 相似文献
997.
The power of energy‐resolved tandem mass spectrometry experiments for resolution of isomers: the case of drug plasma stability investigation of multidrug resistance inhibitors
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