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Cover Picture: Isomerization of Keggin Al13 Ions Followed by Diffusion Rates (Chem. Eur. J. 52/2016)
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Synthesis,characterization and X‐ray shielding properties of polypyrrole/lead nanocomposites
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Novel radiation shielding nanocomposites based on a conducting polymer were fabricated and investigated to determine their abilities in attenuation of X‐rays. Polypyrrole/Pb nanocomposites were prepared through chemical reduction of lead salt by a facile solution‐phase method using t‐BuOLi‐activated LiH and in situ chemical polymerization of pyrrole in the presence of dodecyl benzene sulfonic acid as dopant and surfactant and iron chloride as the oxidant. The morphology, composition, and electrical conductivity of resulting products were characterized by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction analysis, energy‐dispersive X‐ray spectroscopy, fourier transform infrared spectroscopy, and standard four‐wire technique, respectively. In order to evaluate capability of nanocomposites in radiation shielding, X‐ray photon interaction parameters such as linear attenuation coefficient, attenuation percentage, and half‐value thickness were determined for the samples with different Pb loadings and thicknesses, at photon energies of 13.95, 17.74, 20.08, 26.34, and 59.50 keV. The investigation was carried out to explore the potential of polypyrrole/Pb nanocomposites as thin and light‐weight radiation shielding materials. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Farrokh Gharib Noushin Osouleddini Karim Zare Saeed Taghvaei-Ganjali 《Russian Journal of Inorganic Chemistry》2010,55(3):434-437
The synthesis and complexive abilities of 5,11,17-tris(tert-butyl)-23 amino-25,26,27,28-tetra-propoxycalix[4]arene towards
alkali cations Li+, Na+, K+, Rb+, Cs+ and alkali earth cations Mg2+, Ca2+, Sr2+ and Ba2+ in methanol-chloroform mixture have been evaluated at 25°C, using UV-Vis spectrophotometric techniques. The results showed
that the ligand is capable to complex with all the cations by 1: 1 metal to ligand ratios. The selectivity presented considering
the calculated formation constants are in the order Li+ > Na+ > K+ > Rb+ > Cs+ and Mg2+ > Ca2+ > Sr2+ > Ba2+ with the ligand. 相似文献
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Noushin Delmdahl 《Nachrichten aus der Chemie》2006,54(5):552-553
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A sensitive and reproducible stir bar sorptive extraction and HPLC-UV detection method was used for the therapeutic drug monitoring of chlorpromazine and trifluoperazine in human serum. The separation was achieved using a C(18) column. The mobile phase consisted of methanol/sodium acetate buffer (pH 4.1; 0.1 M) (95:5, v/v) including 0.5% triethylamine. This miniaturized method can result in faster analysis, lower solvent consumption and less workload per sample while maintaining or even improving sensitivity. In the second part, stir bar sorptive extraction/HPLC-UV method was optimized by a chemometrics approach. An experimental design was therefore used to evaluate the statistically influential and/or interacting factors, among those described in the literature, and to find the best extraction and desorption conditions. Optimal sample volume of 1 mL, extraction time of 24 min at 31°C with pH 8.1 were obtained in a screening 2(5) half fractional factorial design followed by a Box-Behnken design. For the desorption conditions, a Box-Behnken design showed that the best conditions were 150 μL mobile phase for 20 min at 50°C. The optimized method was repeatable (CV<10%, linear (LOQ-500 ng/mL)), with the LOQs equal to 0.7 and 1.5 ng/mL for chlorpromazine and trifluoperazine, respectively. 相似文献