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271.
Laleh Adlnasab Homeira Ebrahimzadeh Ali Akbar Asgharinezhad Mahnaz Nasiri Aghdam Ali Dehghani Sousan Esmaeilpour 《Food Analytical Methods》2014,7(3):616-628
New functionalized magnetic nanoparticles as solid-phase sorbent were prepared and investigated for extraction of ultra-trace amounts of mercury from environmental samples. The Fe3O4 magnetic nanoparticles functionalized with dithizone were characterized by Fourier transform infrared spectrometer. X-ray diffraction and scanning electron microscopy confirmed the size of nanoparticles. Effects of several factors on the extraction procedure were investigated. The optimized conditions were established to be 80 mg of polymer, 8.5 for solution pH, 5 min for adsorption time, 5 min for desorption time, 2 mL for HCl (0.1 mol L?1)/ thiourea 0.05 % as the eluent, 500 mL for breakthrough volume, and without addition of salt. Under the optimal conditions, the limit of detection, maximum capacity, and preconcentration factor were 0.05 ng mL?1, 0.557 mmol g?1, and 250, respectively. Limit of quantification was in the range of 0.2–2 ng mL?1 for various matrices. Accuracy and precision of the method were about ±2.0 and below 11.1 %, respectively. Finally, the present method has been successfully applied to mercury determination in table salt, green tea, vegetables, toothpaste, and water samples. The mercury content found in the real samples was from 0.6 to 15.74 ng mL?1 without addition of mercury. 相似文献
272.
Sepide Heydari Mohammad Ali Tavanaie Majid Montazer Mahnaz Mahmoudi-Rad 《应用聚合物科学杂志》2024,141(4):e54861
In this research the CuO nanoparticles were synthesized with four different methods then used to produce polyethylene terephthalate (PET) fibers with antibacterial, antifungal, and photocatalytic properties during the melt spinning process. Nanoparticles were synthesized in different ways using copper acetate salt (Cu(CH3COO)2) and sodium hydroxide (NaOH). The synthesis of copper oxide (CuO) nanoparticles was confirmed by field-emission scanning electron microscopy (FE-SEM images), EDX patterns, TGA, FTIR, X-ray diffraction pattern XRD, and UV-vis absorption spectrum. The results showed that synthesized nanoparticles exhibited strong antibacterial activity against gram-positive and gram-negative bacteria. Finally, after examining the fibers with different percentages of nanoparticles), fibers containing 1% of nanoparticles were produced using a 20% nanocopper oxide masterbatch as the optimal sample. The presence of nanoparticles in the fiber structure was confirmed by FE-SEM images, EDX, XRD, and FTIR analysis. Furthermore, the tensile properties, thermal behavior, and photocatalytic properties of the fibers were investigated. Evaluation of the antibacterial and antifungal activity of the produced fibers against gram-positive bacteria Staphylococcus aureus and Candida albicans fungus showed about 90% death of bacteria and fungi. 相似文献
273.
Sheila Shahidi Firoozmehr Mazaheri Bahareh Moazzenchi Homa Hoseini 《Journal of Natural Fibers》2018,15(5):731-739
In this study, the cotton fabrics were modified with dielectric barrier discharge (DBD). Untreated and DBD-treated cotton fabrics were printed with magnetic nanoparticles (γ-Fe2O3 nanoparticles). Argon was used as the working gas. The crystal structure, morphology, and magnetic nature of printed fabrics were investigated by X-ray diffraction, Scanning Electron Microscopy, and vibrating-sample magnetometry (VSM). The catalytic activity of the treated samples for wastewater treatment was studied. The effect of γ-Fe2O3 nanoparticles on the antibacterial activity of DBD-treated cotton fabric was also investigated. The results showed that DBD-treated samples can absorb more nanoparticles than untreated samples. The antibacterial activity of the DBD/γ-Fe2O3-treated samples, which was analyzed by the bacteria counting test, was increased considerably. 相似文献
274.
Farhadi Ladan Mohtashami Mahnaz Saeidi Jafar Azimi-nezhad Mohsen Taheri Ghadir Khojasteh-Taheri Roshanak Rezagholizade-Shirvan Alieh Shamloo Ehsan Ghasemi Ahmad 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(5):1637-1649
Journal of Inorganic and Organometallic Polymers and Materials - The production of silver nanoparticles (AgNPs) using chemical synthesis routes require hazardous and toxic solvents. Nowadays, there... 相似文献
275.
276.
Journal of Computational Electronics - Fe2TiO5, pseudobrookite, with a high Seebeck coefficient and very low thermal conductivity, shows promising thermoelectric properties. However, due to its low... 相似文献