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971.
Fatemeh Ebrahimi Fakhreddin Ashrafizadeh 《Journal of Sol-Gel Science and Technology》2018,85(3):621-628
Mg–Ti substituted strontium hexa-ferrites nanopowders (SrFe12?x(MgTi)x/2O19, x?=?0–3) were prepared by the sol–gel method. The morphology, structure and composition of the nanostructures were examined by field emission scanning electron microscopy (FESEM) and X-ray diffraction. The effect of Mg–Ti doping on the magnetic properties of the powders was investigated by vibrating sample magnetometry (VSM) and ferromagnetic resonance (FMR) at ambient temperature. Experimental results showed that the materials exhibit hexagonal structures with tunable magnetic properties. The saturation magnetization and the coercive field (Hc) decreased through the Mg and Ti substitution. FMR proved that by incorporation of Mg and Ti in strontium ferrite lattice, crystalline anisotropy, and microwave absorption can be tuned. SrFe12?x(MgTi)x/2O19 ferrites are good candidate for applications at X-band microwave frequencies. A low field absorption signal was observed with the same phase as the FMR absorption in all doped ferrites. 相似文献
972.
Mostafa Khajeh Ali Akbar Moosavi‐Movahedi Mohammad Shakeri Fatemeh Musavi Zadeh Ahmad Khajeh Mousa Bohlooli 《Journal of Chemometrics》2015,29(4):245-252
In this study, dispersive solid phase extraction combined with dispersive liquid–liquid extraction has been developed for the extraction of benzene, toluene, ethylbenzene, and xylenes isomers (BTEX) in soil samples prior to gas chromatography–mass spectrometry. The BTEX were extracted from soil sample into acetonitrile by dispersive solid phase extraction method, and the extract was then used as dispersive solvent in dispersive liquid–liquid extraction procedure. Ant colony optimization–artificial neural network (ACO–ANN) has been employed to develop the model for simulation and optimization of this method. The volume of dispersive solvent, volume of extraction solvent, extraction time, and ultrasonic time were the input variables, while the multiple response function (Rm) of analytes was the output. The optimum operating condition was then determined by ant colony optimization method. At the optimum conditions, the limit of detections of 0.12–0.75 ng g−1 was obtained for the BTEX. The developed procedure was then applied to the extraction and determination of BTEX in the soil samples and one certified soil. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
973.
One-pot synthesis of organo-silica hybrids with high thermal properties via a simple sol–gel process
Javanbakht Fatemeh Razavi Bahareh Salami-Kalajahi Mehdi Roghani-Mamaqani Hossein Ommati Masoud 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2267-2274
Journal of Thermal Analysis and Calorimetry - Organic–inorganic hybrid composites have received much attention of scientists in the recent years due to the notable improvement of thermal... 相似文献
974.
Motaharesadat Hosseini Karim Dadashi‐Noshahr Maryam Islami Ehsan Saburi Amin R. Nikpoor Amir Mellati Majid Mossahebi‐Mohammadi Fatemeh Soleimanifar Seyed E. Enderami 《先进技术聚合物》2020,31(8):1857-1864
Using stem cells to replace the lost beta cells is a hopeful strategy in the treatment of diabetic patients. Furthermore, during stem cell culture and therapy, it is a need to use a substrate to act as a supportive matrix to mimic 3D in vivo microenvironment. Therefore, in this study, human adipose‐derived stem cells were used to differentiate into insulin‐producing cells (IPCs) on a silk/polyethersulfone (PES) scaffold. After exposing to the differentiation media, 2D and 3D (silk/PES) cultured cells were gradually aggregated and formed spherical shaped clusters. The viability of cells was comparable in both 3D and 2D culture. As the results of gene expression assay in both RNA and protein level showed, the differentiation efficiency was higher in 3D culture. Furthermore, ELISA revealed that the release of C‐peptide and insulin was higher in 3D than 2D culture. It seems that silk/PES nanofibrous hybrid scaffold could provide an appropriate matrix to mimic in vivo microenvironment and therefore increases the IPC differentiation potency of stem cells. 相似文献
975.
Maryam Kaabipour Saeid Khodadoust Fatemeh Zeraatpisheh 《Journal of separation science》2020,43(5):912-919
In this work, core/shell magnetic molecularly imprinted polymer nanoparticles were synthesized for extraction and pre‐concentration of valsartan from different samples and then it was measured with high‐performance liquid chromatography. For preparation of molecularly imprinted polymer nanoparticles, Fe3O4 nanoparticles were coated with tetraethyl orthosilicate and then functionalized with 3‐(trimethoxysilyl) propyl methacrylate. In the next step, molecularly imprinted polymer nanoparticles were synthesized under reflux and distillation conditions via polymerization of methacrylic acid, valsartan (as a template), azobisisobutyronitrile and ethylene glycol dimethacrylate as cross linking. The properties of molecularly imprinted polymer nanoparticle were investigated by FTIR spectroscopy, field emission scanning electron microscopy, and X‐ray diffraction. Box‐Behnken design with the aid of desirability function was used for optimizing the effect of variables such as the amounts of molecularly imprinted polymer nanoparticles, time of sonication, pH, and volume of methanol on the extraction percentage of valsartan. According to the obtained results, the affecting variables extraction condition were set as 10 mg of adsorbent, 16 min for sonication, pH = 5.5 and 0.6 mL methanol. The obtained linear response (r2 > 0.995) was in the range of 0.005–10 µg/mL with detection limit 0.0012 µg/mLand extraction recovery was in the range of 92–95% with standard deviation less than 6% (n = 3). 相似文献
976.
Kalhor Mehdi Zarnegar Zohre Janghorban Fatemeh Mirshokraei S. Ahmad 《Research on Chemical Intermediates》2020,46(1):821-836
Research on Chemical Intermediates - In the current study, a new catalytic system based on Fe3O4 nanoparticles immobilized on zeolite-SO3H (Fe3O4@zeolite-SO3H) is introduced. In the first stage,... 相似文献
977.
Heravi Majid M. Janati Fatemeh Zadsirjan Vahideh 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):439-482
Monatshefte für Chemie - Chemical Monthly - The Knoevenagel condensation reaction is a prominent organic reaction commonly being utilized in the total synthesis of natural and biologically... 相似文献
978.
Masoumeh Vafaei-Nezhad Ghiasi Reza Shafiei Fatemeh 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(4):772-777
Russian Journal of Physical Chemistry A - This research aimed at exploring the stabilities of the conformers of 2-methoxy-2-oxo-1,3,2-dioxaphosphorinane and its methylthio and methylselenyl analogs... 相似文献
979.
Let \(\mathfrak{A }\) be a Banach \(*\) -algebra and let \(\varphi \) be a nonzero self-adjoint character on \(\mathfrak{A }\) . For a \(*\) -representation \(\pi \) of \(\mathfrak{A }\) on a Hilbert space \(\mathcal{H }\) , we introduce and study strong \(\varphi \) -amenability of \(\pi \) in terms of certain states on the von Neumann algebra of bounded operators on \(\mathcal{H }\) . We then give some characterizations of this notion in terms of certain positive functionals on \(\mathfrak{A }\) . We finally investigate some hereditary properties of strong \(\varphi \) -amenability of Banach algebras. 相似文献
980.
Fatemeh Vahdati Rad Mohammad Reza Housaindokht Razieh Jalal Hossein Eshtiagh Hosseini Asma Verdian Doghaei Sadegh Sadeghi Goghari 《Journal of fluorescence》2014,24(4):1225-1234
Blocking the division of tumor cells by small-molecules is currently of great interest for the design of new antitumor drugs. The interaction of a new metal complex with DNA was investigated through several techniques. Absorption spectroscopy and gel electrophoresis studies on the interaction of the Cu-complex of (2a-4mpyH)2 [Cu(pyzdc)2 (H2O)2].6 H2O with DNA have shown that this complex can bind to CT-DNA with binding constant 3.99?×?105 M?1. The cyclic voltammetry (CV) responses of the metal complex in the presence of CT-DNA have shown that the metal complex can bind to CT-DNA through partial intercalation mode and this is consistent with molecular docking analysis, quenching process and thermal denaturation experiments. The cytotoxicity of this complex has been evaluated by MTT assay. The results of cell viability assay on DU145 cell line revealed that the metal complex had cytotoxic effects. 相似文献