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81.
Masoud Salavati-Niasari Ghader Hosseinzadeh Omid Amiri 《Journal of Cluster Science》2012,23(2):459-468
In this work, monodisperse nanoparticles and nanorods of lanthanum hydroxide was synthesized from the reaction of lanthanum(III) nitrate and sodium hydroxide by sonochemical method. The effect of some of the parameters such as feeding rate of precursors, different solvents of reaction, time of sonication, and various surfactants on the particle size and morphology of products was studied. The as-prepared products were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy. 相似文献
82.
A combined GC-MS with the headspace solid-phase microextraction (SPME) method has been employed for the analysis of the flavor
volatiles of two modified Iranian rice cultivars during gelatinization. In order to optimize the different experimental parameters,
the effect of fiber composition, water content of the rice samples, and equilibrium time were investigated. As a result, while
gelatinization progresses, the amount of volatile compounds would increase as well. Therefore, a broad range of the flavor
volatiles of rice could be extracted, concentrated, and identified. Altogether, 54 and 66 components were identified for HD5
and HD6 rice samples, respectively, of which 33 unique compounds were not detected previously. The identified volatile components
in the modified cultivars belong to the chemical classes of aldehydes, ketones, alcohols, and heterocyclic compounds, phenolic
compounds, and hydrocarbons. 相似文献
83.
We used the cluster structure properties of the 212Po to estimate the neutron skin thickness of 208Pb.For this purpose,we considered two important components:(a)alpha decay is a low energy phenomenon;therefore,one can expect that the mean-field,which can explain the ground state properties of 212Po,does not change during the alpha decay process.(b)212Po has a high alpha cluster-like structure,two protons and two neutrons outside its core nucleus with a double magic closed-shell,and the cluster model is a powerful formalism for the estimation of alpha decay preformation factor of such nuclei.The slope of the symmetry energy of 208Pb is estimated to be 75±25 MeV within the selected same mean-fields and Skyrme forces,which can simultaneously satisfy the ground-state properties of parent and daughter nuclei,as their neutron skin thicknesses are consistent with experimental data. 相似文献
84.
Mohammad Reza Khodabakhshi Firouz Matloubi Moghaddam Mostafa Kiamehr 《Tetrahedron letters》2018,59(51):4503-4508
A simple procedure for the synthesis of dipyrazolo[1,5]diazocine-3,8-diones was developed via the one-pot reaction of 3-aminopyrazolone with substituted benzaldehydes in the presence of catalytic p-toluenesulfonic acid (PTSA). 相似文献
85.
Saeidian Hamid Sadighian Hamed Arabgari Masomeh Mirjafary Zohreh Ayati Seyed Ebrahim Najafi Ezzatollah Moghaddam Firouz Matloubi 《Research on Chemical Intermediates》2018,44(1):601-612
Research on Chemical Intermediates - We report robust green synthesis of novel 1,2,3-triazole-based sulfonamides bearing different motifs such as fluorine under click conditions in presence of a... 相似文献
86.
R. Amiri Dehkharghani M. Zandi Doust M. Tavassoti Kheiri H. Hossein Shahi 《Russian Journal of Applied Chemistry》2018,91(7):1165-1171
The goal of this research is to evaluate the impact of different parameters on corticosteroids entrapment in biocompatible poly-ε-caprolactone nanoparticles. These findings provide better insight on the designing carriers for drugs. Nanocapsules were synthesized by interfacial deposition and their morphology was determined by SEM. Drug entrapment efficiency and particle size distribution were assayed by HPLC and DLS, respectively. The samples were assessed for cytotoxicity using MTT reduction assay. The anti-inflammatory effect of the formulated drug was determined by induction of inflammation in treated as well as native laboratory animals. Statistical analysis of the data was performed using SPSS 18.0. 相似文献
87.
Omid Sadeghi Mehran Amiri Dr. Eric W. Reinheimer Prof. Dr. May Nyman 《Angewandte Chemie (International ed. in English)》2018,57(21):6247-6250
Metal oxo clusters and metal oxides assemble and precipitate from water in processes that depend on pH, temperature, and concentration. Other parameters that influence the structure, composition, and nuclearity of “molecular” and bulk metal oxides are poorly understood, and have thus not been exploited. Herein, we show that Bi3+ drives the formation of aqueous Fe3+ clusters, usurping the role of pH. We isolated and structurally characterized a Bi/Fe cluster, Fe3BiO2(CCl3COO)8(THF)(H2O)2, and demonstrated its conversion into an iron Keggin ion capped by six Bi3+ irons ( Bi6Fe13 ). The reaction pathway was documented by X‐ray scattering and mass spectrometry. Opposing the expected trend, increased cluster nuclearity required a pH decrease instead of a pH increase. We attribute this anomalous behavior of Bi/Fe(aq) solutions to Bi3+, which drives hydrolysis and condensation. Likewise, Bi3+ stabilizes metal oxo clusters and metal oxides in strongly acidic conditions, which is important in applications such as water oxidation for energy storage. 相似文献
88.
Sajjad Abbasi Ali Sarafraz-Yazdi Amirhassan Amiri Ferial Ghaemi 《Journal of the Iranian Chemical Society》2018,15(1):153-161
We describe a magnetic nanocomposite that consists of Fe3O4/carbon nanosphere/polypyrrole (Fe3O4/CNS/PPy). The synthesized nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The nanocomposite was successfully applied to extract of the polycyclic aromatic hydrocarbons (PAHs) from water samples. Compared to Fe3O4/PPy, the Fe3O4/CNS/PPy nanocomposite exhibits improved properties in terms of extraction. The amount of adsorbent, salt effect, extraction time, desorption time, type, and the volume of desorption solvent were optimized. Following the desorption of the extracted analytes, the PAHs (i.e., naphthalene, 2-methylnaphthalene, 2-bromonaphthalene, fluorene, and anthracene) were quantified by gas chromatography–flame ionization detector. The PAHs can be determined in 0.05–100.00 ng mL?1 concentration range, with limits of detection (at an S/N ratio of 3) ranging from 0.01 to 0.05 ng mL?1. The repeatability of the method was investigated with relative standard deviations of lower than 9.9% (n = 5). Also, the recoveries from spiked real water samples were in the range of 88.9–99.0%. The results indicate that the novel material can be successfully applied for the extraction and analysis of PAHs from water samples. 相似文献
89.
A multi-walled carbon nanotube paste electrode (MWCPE) is prepared as an electrochemical sensor with high sensitivity and
selectivity in responding to isoniazid. The electrochemical oxidation of isoniazid is investigated in buffered solution by
cyclic and differential pulse voltammetry. The electrode is shown to be very effective for the detection of isoniazid in the
presence of other biological reductant compounds. The electrochemical oxidation of cysteine, due to the high overvoltage,
is completely stopped at the surface of MWCPE. The electrode exhibits a very good resolution between the voltammetric peak
of isoniazid and the peaks of ascorbic acid (AA) and dopamine (DA). A resolution of more than 450 mV between the anodic peak
potentials makes the MWCPE suitable for simultaneous detection of isoniazid in the presence of AA or DA in clinical and pharmaceutical
preparations. Differential pulse voltammetry (DPV) is applied as a sensitive method for the determination of isoniazid. The
linear range in these determinations is 1 × 10−6–1 × 10−3 M for isoniazid and the detection limit is 5 × 10−7 M. The electrode was applied to the simultaneous determinations in isoniazid and AA mixtures and also, isoniazid and DA mixture
over a wide concentration range. The slope variation for the calibration curves of isoniazid (RSD) was less than 4.5% (based
on ten measurements over a period of three months). 相似文献
90.