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491.
A novel Schiff base, 4‐bromo‐2‐[(2‐[(5‐bromo‐2‐hydroxyphenyl)methylene]amino‐5‐nitrophenyl)iminomethyl]phenol (M1) was synthesized from the reaction of 5‐brom‐salicylaldehyde with 4‐nitro‐o‐phenylenediamine. Schiff base–metal complex was synthesized from the reaction of 4‐bromo‐2‐[(2‐[(5‐bromo‐2‐ hydroxyphenyl)methylene]amino‐5‐nitrophenyl)iminomethyl]phenol (M1) with copper (II) acetate monohydrate [(CH3COO)2 Cu · H2O] salt. Poly‐ (M1‐Cu‐TDP) was synthesized from the reaction of M1‐Cu with 4,4′‐dithiodiphenol (TDP). Poly(M1‐Cu‐PDP) was synthesized from the reaction of M1‐Cu with 4,4′‐propane‐2,2‐diyldiphenol (PDP). Poly(M1‐Cu‐HDP) was synthesized from the reaction of M1‐Cu with 4,4′‐(1,1,1,3,3,3‐hexafluoropropane‐2,2‐di‐yl)diphenol (HDP). The structures of the synthesized monomer and chelate polymers were confirmed by FT‐IR, UV–Vis, 1H‐ and 13C‐NMR, and elemental analysis. The characterization was made by TGA‐DTA, DSC, size exclusion chromatography, cyclic voltammetry, and solubility tests. Also, surface morphologies of chelate polymers were investigated by scanning electron microscope. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
492.
U?ur?Tamer Yusuf?Gündo?du ?smail?Hakk??Boyac? Kadir?Pekmez 《Journal of nanoparticle research》2010,12(4):1187-1196
The production of monodispersed magnetic nanoparticles with appropriate surface modification has attracted increasing attention
in biomedical applications including drug delivery, separation, and purification of biomolecules from the matrices. In the
present study, we report rapid and room temperature reaction synthesis of gold-coated iron nanoparticles in aqueous solution
using the borohydride reduction of HAuCl4 under sonication for the first time. The resulting nanoparticles were characterized with transmission electron microscopy
(TEM), electron spectroscopy for chemical analysis (ESCA), ultraviolet visible spectroscopy (UV–Vis), and X-ray diffraction
(XRD). Surface charges and magnetic properties of the nanoparticles were also examined. The pattern of Fe3O4 nanoparticles is face centered cubic with an average diameter of 9.5 nm and the initial reduction of gold on the surface
of Fe3O4 particles exhibits uniform Fe3O4–Au nanoparticles with an average diameter of 12.5 nm. The saturation magnetization values for the uncoated and gold-coated
Fe3O4 nanoparticles were found to be 30 and 4.5 emu/g, respectively, at 300 K. The progression of binding events between boronic
acid terminated ligand shell and fructose based on the covalent bonding interaction was measured by absorbance spectral changes.
Immunomagnetic separation was also performed at different E. coli concentration to evaluate capturing efficiency of resulting nanoparticles. Immunomagnetic separation percentages were varied
in a range of 52.1 and 21.9% depend on the initial bacteria counts. 相似文献
493.
For the computation of the macroscopic tangent that is required in multiscale volumetric homogenization techniques, two methods are summarized. First, a condensation approach is followed where the linearity of variational terms associated with the penalty enforcement of boundary conditions is explored in order to extract a macroscopic tangent at any stage of the Newton–Raphson iterations of a microstructural testing procedure. As an alternative approach, a second method is explored that requires only the knowledge of infinitesimally close macroscopic deformation states. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
494.
Two different classes of drugs were selected to test the adsorption capacity of carbon nanofibers as a greener new generation alternative adsorbent in simulated gastric and intestinal fluids. Kinetics of the promethazine and trimethoprim adsorption were analyzed using Lagergren first order and Pseudo second order models. Intraparticle diffusion graphs were also plotted to discuss the adsorption mechanism. Kinetic data showed the significance of boundary layer effect for both of the drugs and the presence of intraparticle diffusion as the other rate controlling step for the promethazine adsorption. Giles isotherms showed the high affinity of drug molecules to the adsorbent. Maximum adsorption capacity of drugs was calculated using Langmuir model as 18.35 and 41.15 mg/g for trimethoprim and 95.24 and 80.65 mg/g for promethazine in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), respectively. Trimethoprim adsorption was under favor of hydrophobic interaction and π-π dispersion interactions while promethazine adsorption was through cation exchange where the electrostatic attraction is an important force with the contribution of dispersion interactions. 相似文献
495.