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91.
Mohammad Behbahani Mozhgan Barati Majid Kalate Bojdi Ali Reza Pourali Akbar Bagheri Nasim Akbari Ghareh Tapeh 《Mikrochimica acta》2013,180(11-12):1117-1125
We describe a nanosized Cd(II)-imprinted polymer that was prepared from 4-vinyl pyridine (the functional monomer), ethyleneglycol dimethacrylate (the cross-linker), 2,2′-azobisisobutyronitrile (the radical initiator), neocuproine (the ligand), and Cd(II) (the template ion) by precipitation polymerization in acetonitrile as the solvent. The imprinted polymer was characterized by X-ray diffraction, thermogravimetric analysis, differential thermal analysis, and scanning electron microscopy. The maximum adsorption capacity of the nanosized sorbent was calculated to be 64 mg g?1. Cadmium(II) was then quantified by FAAS. The relative standard deviation and limit of detection are 4.2 % and 0.2 μg L?1, respectively. The imprinted polymer displays improve selectivity for Cd(II) ions over a range of competing metal ions with the same charge and similar ionic radius. This nanosized sorbent is an efficient solid phase for selective extraction and preconcentration of Cd(II) in complex matrices. The method was successfully applied to the trace determination of Cd(II) in food and water samples. Figure
We describe a nanosized ion-imprinted polymer (IIP) for the selective preconcentration of Cd(II) ions. The nanosized-IIP was characterized by X-ray diffraction, Fourier transform IR spectroscopy, thermogravimetric and differential thermal analysis, and by scanning electron microscopy. 相似文献
92.
The dynamic behaviors of several moving cracks in a functionally graded piezoelectric (FGP) strip subjected to anti-plane mechanical loading and in-plane electrical loading are investigated. For the first time, the distributed dislocation technique is used to construct the integral equations for FGP materials, in which the unknown variables are the dislocation densities. With the dislocation densities, the field intensity factors are determined. Moreover, the effects of the speed of the crack propagation on the field intensity factors are studied. Several examples are solved, and the numerical results for the stress intensity factor and the electric displacement intensity factor are presented graphically finally. 相似文献
93.
A -way Latin trade of volume is a collection of partial Latin squares , containing exactly the same filled cells, such that, if cell is filled, it contains a different entry in each of the partial Latin squares, and such that row in each of the partial Latin squares contains, set-wise, the same symbols, and column likewise. It is called a -way-homogeneous Latin trade if, in each row and each column, , for , contains exactly elements, and each element appears in exactly times. It is also denoted as a Latin trade, where is the size of the partial Latin squares.We introduce some general constructions for -way -homogeneous Latin trades, and specifically show that, for all , , and , and for all , (except for four specific values), a -way -homogeneous Latin trade of volume exists. We also show that there is no Latin trade and there is no Latin trade. Finally, we present general results on the existence of -way -homogeneous Latin trades for some modulo classes of . 相似文献
94.
Rouhalla Bagheri Khirud B. Chakraborty Gerald Scott 《Polymer Degradation and Stability》1983,5(3):197-203
The effectiveness of galvinoxyl (G·(I)) as a thermal antioxidant in polypropylene at 140°C is dependent on the prior processing treatment of the polymer. A characteristic fluctuation of antioxidant activity with time of processing is shown to be associated with the extent of conversion of galvinoxyl to hydrogalvinoxyl (GH) in the polymer. It is concluded that the main stabilisation mechanism involved is deactivation of alkylperoxyl radicals (CB-D) by GH but secondary processes (CB-D and CB-A) involving G· may also make a contribution. 相似文献
95.
A pyrrole-based polymer was synthesized and applied as a new sorbent for solid-phase extraction (SPE) of some environmental pollutants from water samples. Polypyrrole (PPy) was synthesized by chemical oxidation of the monomer in nonaqueous solution. SPE of selected phenols, pesticides, and polyaromatic hydrocarbons (PAHs) from aqueous samples were performed using 200 mg PPy. The determination was subsequently carried out by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The polymer showed much higher recoveries for aromatic compounds than aliphatics. Preconcentration of sample volumes up 11 led to acceptable recoveries for aromatic and other tested polar compounds. The R.S.D. for a river water sample spiked with phenols, pesticides and PAHs at sub-ppb level was lower than 10% (n = 3) and limits of detection for these compounds were between 15 and 120 ng l(-1). 相似文献
96.
Seyed M. Bagheri 《Mathematical Logic Quarterly》2006,52(2):125-133
We prove some preservation theorems concerning inductive and model‐complete theories in the framework of semi‐classical logic introduced in [1]. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
97.
Hamid R.?MemarianEmail author Mohammad?Bagheri Dietrich?D?pp 《Monatshefte für Chemie / Chemical Monthly》2004,135(7):833-838
Summary. In continuation of previous work some novel 3,5-diacetyl-1,4-dihydropyridine derivatives were synthesized and their photochemical behavior was studied under oxygen and argon atmosphere. Oxidation of the dihydropyridine ring and formation of pyridine derivatives was the result of the reaction. The presence of oxygen affects not only on the rate of oxidation, but also the formation of some unidentified by-products was observed on irradiation under this atmosphere. 相似文献
98.
Zahra Abdi Dr. Robabeh Bagheri Dr. Mohammad Reza Mohammadi Prof. Zhenlun Song Dr. Mikaela Görlin Prof. Holger Dau Prof. Dr. Mohammad Mahdi Najafpour 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1330-1336
All studies on oxygen-evolution reaction by Mn oxides in the presence of cerium(IV) ammonium nitrate (CAN) have been so far carried out by synthesizing Mn oxides in the first step. And then, followed by the investigation of the Mn oxides in the presence of oxidants for oxygen-evolution reaction (OER). This paper presents a case study of a new and promising strategy for in situ catalyst synthesis by the adding MnII to either CAN or KMnO4/CAN solution, resulting in the formation of Mn-based catalysts for OER. The catalysts were characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. Both compounds contained nano-sized particles that catalyzed OER in the presence of CAN. The turnover frequencies for both catalysts were 0.02 (mmol /molMn⋅s). 相似文献
99.
Beheshtian Javad Peyghan Ali Ahmadi Bagheri Zargham Kamfiroozi Mohammad 《Structural chemistry》2012,23(5):1567-1572
Structural Chemistry - The interactions between BN nanocluster of B12N12 and small molecules (H2, NO, N2, and CH4) were investigated by using density functional computations, exploiting the... 相似文献
100.
Javad Beheshtian Zargham Bagheri Mohammad Kamfiroozi Ali Ahmadi 《Structural chemistry》2012,23(3):653-657
Adsorption of toxic CO molecule on single-walled aluminum nitride nanotubes (AlNNTs) was investigated using density functional
theory calculations. A detailed analysis of the energetic, geometry, and electronic structure of various CO adsorptions on
the tube exterior surface was performed. In contrast to carbon and BN nanotubes, our results indicated that AlNNTs can strongly
interact with CO molecules. The adsorption energy of the most stable configuration was calculated to be about −0.25 eV. The
Morokuma–Kitaura decomposition for molecular interaction energies was used to investigate the nature of C–Al bond in the most
stable CO–AlNNT complex, demonstrating that electrostatic forces and polarization term are basic factors of attractive interaction
between CO and AlNNT. They provide 37.9 and 40.4% of attractive interaction and charge transfer energies make a little contribution
to the adsorption energy of CO. 相似文献