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Dehshahri Ali Sadeghpour Hossein Kazemi Oskuee Reza Fadaei Mahin Sabahi Zahra Alhashemi Samira Hossaini Mohazabieh Erfaneh 《Journal of nanoparticle research》2014,16(5):1-14
The influence of the hydrophilicity and length of the cation alkyl chain in imidazolium-based ionic liquids on the dispersability of ZnO nanoparticles by ultrasound treatment was studied by dynamic light scattering and advanced rheology. ZnO nanopowder synthesized by chemical vapor synthesis was used in parallel with one commercially available material. Before preparation of the dispersion, the nanoparticles characteristics were determined by transmission electron microscopy, X-ray diffraction, nitrogen adsorption with BET analysis, and FT-IR spectroscopy. Hydrophilic ionic liquids dispersed all studied nanopowders better and in the series of hydrophilic ionic liquids, an improvement of the dispersion quality with increasing length of the alkyl chain of the cation was observed. Especially, for ionic liquids with short alkyl chain, additional factors like nanoparticle concentration in the dispersion and the period of the ultrasonic treatment had significant influence on the dispersion quality. Additionally, nanopowder characteristics (crystallite shape and size as well as the agglomeration level) influenced the dispersion quality. The results indicate that the studied ionic liquids are promising candidates for absorber media at the end of the gas phase synthesis reactor allowing the direct preparation of non-agglomerated nanoparticle dispersions without supplementary addition of dispersants and stabilizers. 相似文献
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Y. Ghasemi M. Tabatabaei Yazdi A. Dehshahri H. Niknahad S. Shokravi M. Amini A. Ghasemian M. A. Faramarzi 《Chemistry of Natural Compounds》2006,42(6):702-705
The potential of Nostoc ellipsosporum for biotransformation of hydrocortisone was studied. The microorganism was isolated during a screening program from soil
samples collected from the paddy fields in the north of Iran and had not been previously examined for this purpose. The biotransformation
yielded 11β,17α,20β, 21-tetrahydroxypregn-4-en-3-one and 11β-hydroxyandrost-4-ene-3,17-dione. Both of the metabolites were purified chromatographically and characterized using instrumental
analyses.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 572–574, November–December, 2006. 相似文献
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