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121.
Mousa Ghaemy Seyed Mojtaba Amini Nasab Mehdi Taghavi Marjan Hassanzadeh 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(9):772-783
A new asymmetric diamine containing diarylimodazole pendant was synthesized from the nucleophilic substitution reaction of 1-fluoro-4-nitrobenzene and 2,4-dihydroxy benzaldehyde in the presence of K2CO3, followed by reaction with benzil and ammonium acetate for the preparation of imidazole ring. This novel diamine was used to prepare poly(amide-ether) (PAE) in reaction with different commercially available dicarboxylic acids via direct polycondensation using triphenyl phosphite and pyridine (Py) as catalyst. The PAEs were fully characterized and their properties such as inherent viscosity, solubility, optical, thermal and kinetics of thermal decomposition, and electrochemical oxidation were investigated. The polymers had inherent viscosity in the range of 0.47–0.65 dL/g and were noncrystalline with excellent solubility in various polar aprotic organic solvents. Their Tg values ranged from 200 to 355°C and 10% weight loss temperature above 450°C in nitrogen and left more than 70% residue at 650°C. The kinetic parameters of thermal degradation such as activation energy, entropy, enthalpy and Gibbs free energy of thermal decomposition have been evaluated using different equations. We also report electrochemical oxidation of the resulting polymers in aqueous solution by using cyclic voltammetry technique on the multi-walled carbon nanotube-modified glassy carbon electrode. 相似文献
122.
Leila Bazargan Abbas Shafiee Mohsen Amini Ebrahim Bakhshi Dezfouli Ebrahim Azizi Seyed Mahmood Ghaffari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):602-609
A series of 4-[2-methyl (or aryl) thiazole-4-yl]-2,6-dimethyl-3,5-diacetyl (or dibenzoyl) 1,4-dihydropyridines were synthesized using a modified Hantzsch reaction involving the condensation of the corresponding aldehyde with acetyl acetone or benzoyl acetone. The preparation of the corresponding aldehydes (2-methylthiazole-4-carboxaldehyde and some 2-arylthiazole-4-carboxaldehydes) was achieved by a simplified protocol of the published synthesis. 相似文献
123.
Kurosh Rad‐Moghadam Abbas Ali Esmaeili Saeid Amini Ghalandarabad Fereshteh Hoseininejad Seyyed Adel Fallah‐Rasoulinejad Samaneh Kiani 《Journal of heterocyclic chemistry》2014,51(6):1791-1796
The titled products comprising of two mutually merged bioactive nucleuses, 2‐aminobenzo[d]thiazole and 2,5‐dihydropyrrole rings, were obtained from the reaction between dialkyl acetylenedicarboxylates and alkyl 2‐(benzo[d]thiazol‐2‐yl)amino‐2‐oxoacetates in the presence of triphenylphosphine at RT. 相似文献
124.
Hamid Amini Moghadam Ali A. Orouji 《Physica E: Low-dimensional Systems and Nanostructures》2011,43(10):1779-1782
In this paper, we report a novel Super Junction Metal Semiconductor Field Effect Transistor (SJ-MESFET) where the drift region consists of a p-type pillar in order to improve breakdown voltage. We demonstrate that the depletion region in the drift region can be extended entirely by the p-type pillar leading to a uniform electric field. Therefore breakdown voltage significantly improves. Using two-dimensional and two-carrier device simulation, we have analyzed the various performance and design considerations of the SJ-MESFET. Also we have explained the reasons for improving the performance of the SJ-MESFET when compared to a Conventional Bulk MESFET (CB-MESFET). Detailed numerical simulations demonstrate that for the proposed structure due to decrease in parasitic gate-to-drain capacitor, maximum oscillation frequency increases with respect to CB-MESFET. 相似文献
125.
Suzuki–Miyaura cross-coupling reactions in water using in situ generated palladium(II)–phosphazane complexes 总被引:1,自引:1,他引:0
Mojtaba Amini Abbas Tarassoli Saeed Yousefi Sepideh Delsouz-Hafshejani Mina Bigdeli Mahnaz Salehifar 《中国化学快报》2014,25(1):166-168
The phosphazane derivatives(L1–3) were readily obtained by reaction of different ratios of PCl3 and PhNH2. The L1–3 derivatives were found to be efficient ligands in the palladium-catalyzed Suzuki C–C coupling reactions in water. It was determined that with the use of L1–3 /Pd(OAc)2 system as a catalyst, aryl halides undergo Suzuki cross-couplings with arylboronic acids to give the desired products in moderate to excellent yields. 相似文献
126.
Application of a magnetic molecularly imprinted polymer for the selective extraction and trace detection of lamotrigine in urine and plasma samples
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Mohammad Behbahani Saman Bagheri Mostafa M. Amini Hamid Sadeghi Abandansari Hamid Reza Moazami Akbar Bagheri 《Journal of separation science》2014,37(13):1610-1616
Magnetic molecularly imprinted polymers have been synthesized for the selective preconcentration and trace determination of lamotrigine (LTG) in urine and plasma samples. The magnetic nanoparticles were modified by tetraethyl orthosilicate and 3‐methacryloxypropyl trimethoxysilane before imprinting. The magnetic molecularly imprinted polymers were prepared via surface molecular imprinting technique, using Fe3O4 as a magnetic component, LTG as template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross‐linker, and 2,2′‐azobisisobutyronitrile as a radical initiator in methanol/acetonitrile (50:50, v/v) as the porogen. The obtained sorbent was characterized using scanning electron microscopy, Fourier‐transform infrared spectroscopy, X‐ray diffraction, and thermal analysis. Separation of the sorbent from the sample solution was simply achieved by applying an external magnetic field. Determination of the extracted drug was performed by high‐performance liquid chromatography with UV detection. Under the optimum extraction conditions, the method detection limits were 0.7 μg/L (based on S/N of 3) for urine samples and 0.5 μg/L for plasma samples. A linear dynamic range of 1–1000 μg/L was obtained for LTF in plasma and urine samples. Finally, the applicability of the proposed method was evaluated by extraction and determination of LTG in urine and plasma samples. 相似文献
127.
Mojtaba Bagherzadeh Mojtaba Amini Parviz Gohari Derakhshandeh Mohammad Mehdi Haghdoost 《Journal of the Iranian Chemical Society》2014,11(2):441-446
The glucose-based ligand, N-salicylidene-d-glucosamine (Sal-d-glsmN), was readily obtained by reaction of salicylaldehyde (Hsal) with the d-glucosamine hydrochloride. Ligand Sal-d-glsmN was found to be an efficient ligand in the palladium-catalyzed Suzuki and Heck C–C coupling reactions in aqueous medium under aerobic condition. It was found that the use of Sal-d-glsmN/Pd(OAc)2 system as a catalyst, aryl halides undergo Suzuki and Heck cross-couplings, respectively, with arylboronic acids and olefins to give the desired products in moderate to excellent yields. 相似文献
128.
Homeira Ebrahimzadeh Elahe Moazzen Mostafa M.Amini Omid Sadeghi 《Mikrochimica acta》2013,180(5-6):445-451
We have developed a gold ion-imprinted polymer (GIP) by incorporating a dipyridyl ligand into an ethylene glycol dimethacrylate matrix which then was coated onto porous silica particles. The material was used for the selective extraction of ultratrace quantities of gold ion from mine stones, this followed by its quantitation by FAAS. The effects of concentration and volume of eluent, pH of the solution, flow rates of sample and eluent, and effect of potentially interfering ions, especially palladium and platinum, was investigated. The limit of detection is <0.2 ng?mL?1, the precision (RSD%) is 1.03 %, and recoveries are >99 %. In order to show the high selectivity and efficiency of the new sorbent, the results were compared to those obtained with more simple sorbents possessing the same functional groups. The accuracy of the method was demonstrated by the accurate determination of gold ions in a certified reference material. To the best of our knowledge, there is no report so far on an imprint for gold ions that has such a selectivity over Pd(II) and Pt(II) ions. Figure
Coating of gold ion imprinted polymer on nanoporous silica 相似文献
129.
Efficient quadrature rules with a priori error estimates for integrands with end point singularities
In this paper we present details of an efficient numerical integration rule based upon error function transformation of the integration variable. We also derive an a priori error estimate for our method and present numerical results to highlight various features of the rule as applied to integrals with end point singularities in the low order derivatives of their integrands. 相似文献
130.
The relation between representations and positive definite functions is a key concept in harmonic analysis on topological groups. Recently this relation has been studied on topological groupoids. This is the first in a series of papers in which we have investigated a similar relation on inverse semigroups. We use a new concept of “restricted” representations and study the restricted semigroup algebras and corresponding C *‐algebras. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献