排序方式: 共有75条查询结果,搜索用时 31 毫秒
31.
Farideh Namvar Susan Azizi Rosfarizan Mohamad Amin Boroumand Moghaddam Mozhgan Soltani Fazele Moshfegh 《Research on Chemical Intermediates》2016,42(3):1571-1581
Palm pollen (PP) has been widely used in nutrition, pharmaceutical and cosmetic industries. In the present study, we explored the potential of PP in the synthesis of a silver nanoparticle (Ag NP). PP was used as both reducing and stabilizing agent. The Ag/PP nanocomposite was examined by field emission electron microscopy, X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet spectroscopy and zeta potential measurement. The biosynthesized NPs showed surface plasmon resonance centered at 425 nm with an average particle size measured to be 23 nm and a zeta potential of ?30.9 mV. Prominent FT-IR signals were obtained and ascribed to phenolic and carbohydrate compounds involved in the formation of the Ag NPs, and proteins which participated in stabilization of the Ag NPs. The biologically synthesized Ag NPs were found to be extremely effective against E. coli (13.8 ± 0.25 mm) with a minimum inhibitory concentration of 20 µg/mL. Thus, such biosynthesized Ag NPs can be used in medicinal applications. 相似文献
32.
A facile procedure was applied to successfully synthesize novel Pd nanoparticles immobilized on triethanolamine-functionalized magnetic nanoparticles [Fe3O4/IL/Pd]. Diverse characterizations (HR-TEM, XRD, FT-IR, TGA, EDX, FE-SEM, ICP, XPS and VSM) were carried out to identify intrinsic traits of the nanoparticles. At room temperature, Fe3O4/IL/Pd demonstrated high catalytic activity toward Suzuki-Miyaura cross-coupling reactions in aqueous solution. Based on the results, Fe3O4/IL/Pd acted as zwitterionic IL-type heterogeneous catalyst, which could be separated from the reaction mixture, conveniently. Moreover, it exhibited excellent recyclability for at least eight cycles without considerable loss of its activity. 相似文献
33.
Khorasani-Motlagh M Noroozifar M Mirkazehi-Rigi S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):978-984
The binding of neodymium(III) and praseodymium(III) complexes containing 1,10-phenanthroline, [M(phen)2Cl3·OH2] (M=Nd (1), Pr (2)), to DNA has been investigated by absorption, emission, and viscosity measurements. The complexes show absorption decreasing in charge transfer band, fluorescence decrement when bound to DNA. The binding constant Kb has been determined by absorption measurement for both complexes and found to be (6.76±0.12)×10(4) for 1 and (1.83±0.15)×10(4)M(-1), for 2. The fluorescence of [M(phen)2Cl3·OH2] (M=Nd (1), Pr (2)) has been studied in detail. The results of fluorescence titration reveal that DNA has the strong ability to quenching the intrinsic fluorescence of Nd(III) and Pr(III) complexes through the static quenching procedure. The binding site number n, apparent binding constant Kb and the Stern-Volmer constant kSV are determined. Thermodynamic parameters, enthalpy change (ΔH°) and entropy change (ΔS°), are calculated according to relevant fluorescent data and Van't Hoff equation. The experimental data suggest that the complexes bind to DNA by non-intercalative mode. Major groove binding is the preferred mode of interaction for [M(phen)2Cl3·OH2] (M=Nd (1), Pr (2)) with DNA. 相似文献
34.
Mozhgan Masoudi Mohammad Reza Shahbazi‐Manshadi Mohammad Anary‐Abbasinejad 《Journal of heterocyclic chemistry》2019,56(10):2772-2778
Heterocyclic systems containing bis (imidazolyl) pyrrole or imidazolyl indole moieties were synthesized by heterocyclization of pyrrole or indole with arylglyoxal monohydrates and N‐aryl amidines in ethanol catalyzed by FeCl3 at room temperature. The paper reports a facile, efficient, and environmentally friendly protocol for the synthesis of new products. Products were isolated by simple filtration, and their structures were established from their spectroscopic data. 相似文献
35.
Shohre Rouhani Kamaladin Gharanjig Mozhgan Hossein Nezhad 《Green Chemistry Letters and Reviews》2014,7(2):174-178
This study describes the ultrasound-assisted synthesis of 4-nitro-N-substituted-1,8-naphthalimide derivatives from 4-nitro-1,8-naphthalic anhydride and related amines by irradiating at 35 KHz in a sonic bath in aqueous media at room temperature. The results obtained by this method are comparable to those obtained by a common reflux method. The imidation reaction under ultrasound irradiation preceded 8 and 20 times faster than the common method and produced higher yields. 相似文献
36.
Szatylowicz Halina Jezuita Anna Siodla Tomasz Varaksin Konstantin S. Ejsmont Krzysztof Shahamirian Mozhgan Krygowski Tadeusz M. 《Structural chemistry》2018,29(4):1201-1212
Structural Chemistry - Substituents effects in cyclic diene derivatives are studied using quantum chemical modeling and compared to the corresponding effects in aromatic (benzene) and fully... 相似文献
37.
Farzaneh Shemirani Seyedeh Mozhgan Behgozin 《Journal of the Iranian Chemical Society》2018,15(9):1907-1912
38.
A flow injection analysis (FIA)-background correction method comprising two solid-phase reactors and spectrophotometry for determination of ascorbic acid (AsA) is proposed. A polyethylene mini-column filled with solid iodine (30% m/m suspended on silica gel beads), reactor 1, and other column filled only with silica gel, reactor 2, which are then incorporated in a flow system so that solid iodine reagent in reactor 1 is affected as the sample passes through the column. The sample blank is produced by the oxidation of the AsA by iodine to form dehydroascorbic acid, insensitive to ultraviolet at 267 nm. AsA in samples is determined after injected in reactor 2; the difference in two analytical signal observed is related to amount of AsA. The linear range of the system is up to 50 μg ml−1 with a detection limit of 0.08 μg ml−1, R.S.D. of better than 1.0% and sampling frequency of 110 sample h−1. The method is successfully applied to the determination of AsA in pharmaceuticals and foods. 相似文献
39.
Safavi A Bagheri M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(4):735-739
The characterization of an optical sensor membrane is described for indirect determination of isoniazid. The sensing membrane was consisted of immobilized 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) on a triacetylcellulose membrane. The procedure is based on the reaction of Fe(III) with isoniazid in the presence of PDT. Fe(III) is reduced by isoniazid to Fe(II) which forms a complex with PDT. The complex shows an absorption maximum at 558nm. By measuring the absorbance of the complex at this wavelength, isoniazid can be determined in the range of 0.62-6.15mugmL(-1). This method was applied to the determination of isoniazid in pharmaceutical formulation and enabled the determination of isoniazid in microgram quantities. 相似文献
40.
Experimental and Theoretical Study of Enhanced Photocatalytic Activity of Mg‐Doped ZnO NPs and ZnO/rGO Nanocomposites 下载免费PDF全文
Dr. Ramin Yousefi Dr. Javad Beheshtian Seyedeh Mozhgan Seyed‐Talebi Dr. H. R. Azimi Dr. Farid Jamali‐Sheini 《化学:亚洲杂志》2018,13(2):194-203
A systematic experimental and theoretical study of the origin of the enhanced photocatalytic performance of Mg‐doped ZnO nanoparticles (NPs) and Mg‐doped ZnO/reduced graphene oxide (rGO) nanocomposites has been performed. In addition to Mg, Cd was chosen as a doping material for the bandgap engineering of ZnO NPs, and its effects were compared with that of Mg in the photocatalytic performance of ZnO nanostructures. The experimental results revealed that Mg, as a doping material, recognizably ameliorates the photocatalytic performance of ZnO NPs and ZnO/graphene nanocomposites. Transmission electron microscopy (TEM) images showed that the Mg‐doped and Cd‐doped ZnO NPs had the same size. The optical properties of the samples indicated that Cd narrowed the bandgap, whereas Mg widened the bandgap of the ZnO NPs and the oxygen vacancy concentration was similar for both samples. Based on the experimental results, the narrowing of the bandgap, the particle size, and the oxygen vacancy did not enhance the photocatalytic performance. However, Brunauer–Emmett–Teller (BET) and Barret–Joyner–Halenda (BJH) models showed that Mg caused increased textural properties of the samples, whereas rGO played an opposite role. A theoretical study, conducted by using DFT methods, showed that the improvement in the photocatalytic performance of Mg‐doped ZnO NPs was due to a higher electron transfer from the Mg‐doped ZnO NPs to the dye molecules compared with pristine ZnO and Cd‐doped ZnO NPs. Moreover, according to the experimental results, along with Mg, graphene also played an important role in the photocatalytic performance of ZnO. 相似文献