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41.
Abstract
An efficient one-pot synthesis of ketenimine derivatives is described. It involves a four-component reaction between benzylamines, 2,2-dichloroethanoyl chloride, alkyl isocyanide, and dialkyl acetylenedicarboxylates under mild conditions at ambient temperature. 相似文献42.
Zahra Hosseinpour Alice Scarpellini Sharif Najafishirtari Dr. Sergio Marras Dr. Massimo Colombo Dr. Abdolali Alemi Dr. Michaël De Volder Dr. Chandramohan George Dr. Vladimir Lesnyak 《Chemphyschem》2015,16(16):3418-3424
Hierarchical superstructures formed by self‐assembled nanoparticles exhibit interesting electrochemical properties that can potentially be exploited in Li‐ion batteries (LIBs) as possible electrode materials. In this work, we tested two different morphologies of CuS superstructures for electrodes, namely, tubular dandelion‐like and ball‐like assemblies, both of which are composed of similar small covellite nanoparticles. These two CuS morphologies are characterized by their markedly different electrochemical performances, suggesting that their complex structures/morphologies influence the electrochemical properties. At 1.12 A g?1, the cells made with CuS tubular structures delivered about 420 mAh g?1, and at 0.56 A g?1, the capacity was as high as about 500 mAh g?1 with good capacity retention. Their ease of preparation and processing, together with good electrochemical performance, make CuS tubular dandelion‐like clusters attractive for developing low‐cost LIBs based on conversion reactions. 相似文献
43.
Mahnaz?Nozohour Yazdi Yadollah?YaminiEmail author Hamid?Asiabi Abdolali?Alizadeh 《Mikrochimica acta》2018,185(11):525
Novel composites were obtained via direct assembly of polysulfides (Sx2?, X?=?3, 4, 6) on the surface of a metal organic framework (MOF; type benzene-1,3,5-tricarboxylic/Cu(II). They are referred to as Sx-MOFs and were used for highly selective and efficient extraction of ultra-trace amounts of heavy metal ions from aqueous solutions. The structure of the Sx-MOFs was characterized by Raman spectroscopy, FT-IR, X-ray diffraction, and scanning electron microscopy. The Raman spectra of Sx-MOF is similar to the bare MOF and shows the MOFs structure to be well retained after Sx functionalization. The selective interaction of Sx with soft metal ions and the high surface area of MOFs resulted in excellent affinity and selectivity for ions such as Hg(II). The Sx-MOFs of type S4-MOF had the highest distribution coefficient Kd value (~107) and best extraction recovery (~100%) for Hg(II). The S4-MOF also has high selectivity in the following order: Hg(II) >?>?Pb(II)?>?Zn(II)?>?Ni(II)?>?Co(II). The binding process of the metals occurs via M–S bonding. The ions were quantified by inductively coupled plasma optical emission spectrometry (ICP-OES). The detection limit for Hg(II) is 0.13 μg L?1. The S4-MOF was applied to the extraction of trace metal ions from natural and contaminated waters and data were compared with other sorbets. The results revealed that S4-MOF is an excellent adsorbent for sorption of heavy metal ions even in the presence of the relatively high concentration of other ions. 相似文献
44.
An effective route to novel 4‐(alkylamino)‐1‐(arylsulfonyl)‐3‐benzoyl‐1,5‐dihydro‐5‐hydroxy‐5‐phenyl‐2H‐pyrrol‐2‐ones 10 is described (Scheme 2). This involves the reaction of an enamine, derived from the addition of a primary amine 5 to 1,4‐diphenylbut‐2‐yne‐1,4‐dione, with an arenesulfonyl isocyanate 7 . Some of these pyrrolones 10 exhibit a dynamic NMR behavior in solution because of restricted rotation around the C? N bond resulting from conjugation of the side‐chain N‐atom with the adjacent α,β‐unsaturated ketone group, and two rotamers are in equilibrium with each other in solution ( 10 ? 11 ; Scheme 3). The structures of the highly functionalized compounds 10 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS), by elemental analyses, and, in the case of 10a , by X‐ray crystallography. A plausible mechanism for the reaction is proposed (Scheme 4). 相似文献
45.
The one-pot synthesis of 2,3-dihydro-1,5-benzodiazepins-2-one bearing phosphanylidene (ylide) or phosphono-succinate substituent is described. In this four-component reaction, benzodiazepine derived from condensation of o-phenylenediamine and diketene is trapped with the trialkyl phosphite-dialkyl acetylenedicarboxylate zwitterion. In the presence of H2O, the ylide functional group is hydrolyzed to the corresponding phosphonate. The configuration of the products is selective and only one of the two possible rotamers or diastereomers is formed exclusively in high yield. 相似文献
46.
Abdolali Ramazani Mohammad Almasi KashiGhafour Seyedi 《Journal of magnetism and magnetic materials》2012
Crystalline Co nanowires were pulse electrodeposited into nanoporous aluminum oxide template having an ultra-thinned barrier layer. The effects of off-time between pulses and electrolyte acidity on the microstructure and magnetic properties of the nanowires were investigated. Increasing the off time between pulses increased the crystallinity and the alignment of easy axis with the wire axis. The rate of these increments was seen to depend on the electrolyte acidity and reached its maximum at pH=5.25 electrolyte acidity. Optimizing the crystallinity and crystal orientation, a coercivity value of 3320 Oe and a squareness of>90% were obtained for pure Co nanowires. A 10% increase in coercivity was found after annealing the samples. 相似文献
47.
Analytical performance evaluation of the OFDM systems in the presence of jointly fifth order nonlinearity and phase noise 总被引:1,自引:0,他引:1
M. H. Madani A. Abdipour A. Mohammadi 《Analog Integrated Circuits and Signal Processing》2011,66(1):103-115
This paper presents an exact theoretical analysis of the performance degradation in an orthogonal frequency division multiplexing (OFDM) system when the signal including phase noise is passed through a nonlinear circuit such as high power amplifier (HPA). This circuit is modeled as a fifth order memory-less nonlinear polynomial model (5th order MLNPM). The nonlinear model is derived from important electrical parameters such as gain, 1-dB compression and 3rd order intercept point. Theoretical analysis shows that the detected data symbol at the receiver consists of attenuated version of the original transmitted data symbol, common phase error (CPE), inter-sub-carrier interference (ICI), third and fifth order intermodulation (IM) components. The analytical expressions for intermodulation noise term are derived using combinatorial methods. By use of the derived expressions, a closed-form output signal to noise ratio (SNR), degradation factor (DF) and probability of error can be evaluated theoretically. For verifying the accuracy of our analysis, comparisons between the theoretical and simulated results with electrical parameter of an actual and applicable HPA are presented. The comparisons show that bit error rate (BER) of analytical results is closely match with simulation results for OFDM system using M-QAM modulation. 相似文献
48.
Abdolali Alizadeh Mohamad Acedi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2601-2606
4,5-dialkyl 1-isopropyl 3-isopropoxy-1H-pyrazole-1,4,5-tricarboxylate was obtained in an excellent yield from the reaction of dialkyl acetylenedicarboxylates and diisopropyl azodicarboxylate in the presence of triphenylphosphine in dry dichloromethane. This reaction provides a useful synthetic route to highly functionalized pyrazoles. 相似文献
49.
An efficient approach for the preparation of functionalized 4-(1,3-dioxo-2,3-dihydro-1H-2-indenyl) substituted 1-benzylpyrrole-3-carboxylates is described. This four-component reaction between ninhydrin, 1-phenyl-2-(1,1,1-triphenyl-λ5-phosphanylidene)-1-ethanone, primary amines and alkyl acetoacetate proceeds in MeOH under reflux condition in good to excellent yields. 相似文献
50.
Reza Zaker Abdolali Abdipour Ahad Tavakoli 《Analog Integrated Circuits and Signal Processing》2014,80(3):507-517
In this paper, a new modified combination of antenna and array feed network integrated in low thickness microstrip technology is presented. A concept similar to the concept of coherently radiating periodic structures is used to feed a 4-element antenna array. In the feed network, a new combination of Gysel-based 3 and 5 port components as power dividers/combiners is employed to propagate the power into the antenna array so that the desired Gaussian-like amplitudes and linear phase distributions can be obtained. These multi-port components are modified to design the feed network by single-layer microstrip technology without the matching and isolation circuits and through-substrate vias. Therefore, the manufacturing cost and difficulty and design complexity are reduced, considerably. Full-wave simulations of the feed network, unit cells and the final integrated antenna array are done, step by step and the results considering all possible losses are presented. To validate the designs, two prototypes, first the feed network and second the integrated module including both antenna array and feed network designed at 3.5 GHz were fabricated and measured and the S parameters (amplitude and phase) were compared with the full-wave simulations. A good agreement between the results including impedance and radiation characteristics is shown. 相似文献