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31.
Green and one‐pot surface coating of iron oxide magnetic nanoparticles with natural amino acids and biocompatibility investigation 下载免费PDF全文
Hamed Nosrati Marziyeh Salehiabar Elahe Attari Soodabeh Davaran Hossein Danafar Hamidreza Kheiri Manjili 《应用有机金属化学》2018,32(2)
We report the synthesis of iron oxide magnetic nanoparticles (IONPs) coated with various natural amino acids (AAs) using a one‐pot reaction in an aqueous medium. Several AAs, which contained hydrophilic and hydrophobic groups, were selected to study their effects on size, morphology and toxicity of IONPs. Functionalized IONPs were characterized using X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning and transmission electron microscopies. Furthermore, vibrating sample magnetometry analysis shows these nanoparticles have excellent magnetic properties. Cellular toxicity of IONPs was also investigated on HFF2 cell lines. The AA‐coated IONPs are non‐toxic and biocompatible. Natural AA‐coated IONPs show a potential for their development in in vitro and in vivo biomedical fields due to their non‐toxicity, good ζ‐potential and related small size and narrow size distribution. 相似文献
32.
Saeed Ketabchi Hossein Moosaei 《Journal of Optimization Theory and Applications》2012,154(3):1080-1087
In this paper, we give an algorithm to compute the minimum norm solution to the absolute value equation (AVE) in a special case. We show that this solution can be obtained from theorems of the alternative and a useful characterization of solution sets of convex quadratic programs. By using an exterior penalty method, this problem can be reduced to an unconstrained minimization problem with once differentiable convex objective function. Also, we propose a quasi-Newton method for solving unconstrained optimization problem. Computational results show that convergence to high accuracy often occurs in just a few iterations. 相似文献
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2‐hydroxyethylammonium formate ionic liquid grafted magnetic nanoparticle as a novel heterogeneous catalyst for the synthesis of substituted imidazoles 下载免费PDF全文
Catalytic one‐pot condensation of benzil, aldehyde and ammonium acetate have been successfully carried out using 2‐hydroxyethylammonium formate (HEAF) grafted on a magnetic nanoparticles as a new heterogeneous catalyst. The as‐prepared catalyst was characterized by FT‐IR, TEM, FESEM, VSM, TGA and XRD. This catalyst indicated significant advantages, such as excellent yields, shorter reaction time, reusability of the catalyst and easy workup process. 相似文献
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Gholam Hossein Zohuri Saman Damavandi Reza Sandaroos 《Research on Chemical Intermediates》2013,39(5):2115-2121
A new and efficient method has been developed for the one-pot synthesis of novel 2,9-dihydro-2-oxo-4-aryl-1H-pyrido[2,3-b]indole-3-carbonitrile derivatives by condensation of substituted (triethoxymethyl)arene, 1-methyl-1H-indol-2-ol and cyanoacetamide in the presence of a catalytic amount of crosslinked poly(2-acrylamido-2-methyl propane sulfonic acid) (AMPS) as an efficient and heterogeneous catalyst. This polymeric solid acid catalyst is stable and can be easily recovered and reused without significant change in its activity. 相似文献
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Synergetic catalytic effect of rGO,Pd, Fe3O4 and PPy as a magnetically separable and recyclable nanocomposite for coupling reactions in green media 下载免费PDF全文
In this paper, rGO/Pd–Fe3O4@PPy as an efficient stable nanocomposite was synthesized. To understand the synergetic effects of rGO, Pd, Fe3O4 and PolyPyrrole, the performance of rGO/Pd–Fe3O4@PPy as a heterogeneous recyclable nanocatalyst in the green synthesis of C‐C and C‐O coupling products, as well as different conditions are studied. Synthesized rGO/Pd–Fe3O4@PPy was characterized by FT‐IR, XRD, FE‐SEM, EDS, TGA and AFM analysis. Best results are obtained under sonication in H2O for C‐C coupling and by ball‐milling for C‐O coupling. The benefits of this method include: green solvents and conditions, absence of external base, low reaction times with high yield and easy work‐up method. 相似文献
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Application of a dispersive micro‐solid‐phase extraction method for pre‐concentration and ultra‐trace determination of cadmium ions in water and biological samples 下载免费PDF全文
Mohammad Behbahani Ali Veisi Fariborz Omidi Aminreza Noghrehabadi Ali Esrafili Mohammad Hossein Ebrahimi 《应用有机金属化学》2018,32(3)
A method for the trace determination of cadmium ions in water, human urine and human blood serum samples using ultrasonic‐assisted dispersive micro‐solid‐phase extraction (UA‐D‐μSPE) was developed. Silica‐coated magnetic nanoparticles were coated with polythiophene, and the resulting sorbent was characterized using thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X‐ray diffraction. Following UA‐D‐μSPE, cadmium ions were quantified using graphite furnace atomic absorption spectrometry. A Box–Behnken design was used for optimization of important sorption and desorption parameters in UA‐D‐μSPE: in the sorption step, pH of solution, sorption amount and sonication time for sorption; in the desorption step, concentration of eluent, volume of eluent and sonication time. The optimum conditions for the method were: pH of solution, 7.5; sonication time for sorption, 3 min; sorption amount, 35 mg; type and concentration of eluent, HCl and 1.1 mol l?1; volume of eluent, 360 μl; sonication time for desorption, 110 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of cadmium ions by UA‐D‐μSPE were found to be 0.8 ng l?1 and <6%, respectively. 相似文献