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31.
Amarnath Bheemaraju Mahshid Pourmand Boqian Yang Sravan K. Surampudi Travis L. Benanti Marc Achermann 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):986-993
We have probed the effect of side chains on the charge transfer dynamics in dyads containing quaterthiophene (QT) donor and naphthalene diimide (NDI) acceptor. The donor and the acceptor are covalently linked using a flexible linker. Four dyads (1–4) were synthesized with the quaterthiophene bearing hexyl side chain and the naphthalene diimide bearing hydrocarbon, fluorocarbon, branched or polar side chains. The UV-Vis spectra for these dyads showed the existence of a donor-acceptor complex. The time-resolved fluorescence (TRF) decay studies show a rapid quenching of fluorescence in all the dyads upon excitation of the donor. We found that the side chains on the NDI did not alter the quenching rates in solution. 相似文献
32.
Kamal AlimohammadiYaghoub Sarrafi Mahmood TajbakhshSaeed Yeganegi Mahshid Hamzehloueian 《Tetrahedron》2011,67(8):1589-1597
The regio- and stereochemical polar [3+2] cycloaddition of the azomethine ylides, which were generated in situ by the reaction of isatin derivatives and proline, with trans-β-nitrostyrene and (E)-1-phenyl-2-nitropropene were studied using experimental and theoretical methods. In comparison with trans-β-nitrostyrene, when the reactions were performed with (E)-1-phenyl-2-nitropropene, a remarkable inversion in the regioselectively was observed. The regioselectivity of the reactions was investigated using global and local reactivity indices and frontier molecular orbital (FMO) analysis at the B3LYP/6-31G(d,p) level of theory. The effects of the electronic and steric factors on the regioselectivity of the reactions were discussed. The inspection of geometries and energetics of transition states revealed the importance of weak interactions in regioselectivity of the cycloaddition reactions. 相似文献
33.
Reduction of a variety of imine compounds with triethylsilane in the presence of catalytic amounts of palladium(II) acetate in ethanol resulted in the formation of the corresponding amines in excellent yields after short reaction times. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
34.
Let ${\mathcal{G}}$ be a group of invertible linear transformations on a finite-dimensional vector space over an algebraically closed field. We show that if ${\mathcal{G}=\mathcal{H}\vee\mathcal{K}}$ , where ${\mathcal{H}}$ is a normal subgroup consisting of singleton spectrum operators and ${\mathcal{K}}$ is a triangularizable subgroup, then ${\mathcal{G}}$ is triangularizable. 相似文献
35.
Maryam Mirza‐Aghayan Mahboubeh Khoshkameh Langrodi Mahshid Rahimifard Rabah Boukherroub 《应用有机金属化学》2009,23(7):267-271
An efficient synthesis of 1,4‐dihydropyridine derivatives has been achieved by the one‐pot cyclocondensation reaction of methyl 3‐aminocrotonate and a range of aldehydes in the presence of chlorotrimethylsilane as a promoter under solvent‐free conditions. The cyclocondenstion reaction requires a very short time and takes place in good to excellent yields. Furthermore iodotriethylsilane, generated in situ by the reaction of triethylsilane and methyl iodide in the presence of palladium chloride, has been investigated for the synthesis of 1,4‐dihydropyridine derivatives. This facile and efficient method affords high yields for the preparation of 1,4‐dihydropyridines at room temperature and short reaction times. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
36.
Mahshid Manouchehri Shahram Seidi Mohammad Taghi Naseri Ahmad Rouhollahi 《Journal of separation science》2022,45(2):594-601
In the present research, a blended polyacrylamide-chitosan hydrogel was synthesized. For the first time, the prepared sorbent was efficiently employed in a hydrogel-based spin-column setup as a promising format. The proposed method was applied for monitoring the trace amounts of ketoconazole, clotrimazole, and miconazole in blood samples. Effective adsorption and desorption parameters were optimized using a central composite design and the one-variable-at-a-time method. Under the optimal conditions, the calibration curves were linear in the range of 15.0–1000.0, 1.0–1000.0, and 2.0–1000.0 ng mL–1 for ketoconazole, clotrimazole, and miconazole, respectively, along with intra- and interday precision less than 8.4%. Limits of detection were obtained between 0.2 and 5.0 ng mL–1. The preconcentration factors were found in the range of 5.9–7.8. The introduced method was successfully applied for micro-solid-phase extraction of trace amounts of target antifungal drugs in blood samples, followed by liquid chromatography-tandem mass spectrometry. Satisfactory relative recoveries of 94.5–103.5% were obtained, implying method reliability. Overall, the proposed method provides good accuracy and repeatability, high reusability, and good applicability to determine antifungal drugs in complex biological matrices. 相似文献
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38.
Sayed Mehdi Ghoreishi Mohsen Behpour Mahshid Golestaneh 《Journal of inclusion phenomena and macrocyclic chemistry》2008,62(3-4):279-284
In this study inclusion of hexadecyltrimethylammonium bromide (HTAB) with α-, and β-cyclodextrin (CD) in the presence and the absence of bromhexine (BH) was investigated using ion-selective electrode method. The association constants of HTAB with CDs were determined by potentiometry and were close to literature values. The obtained results indicated that α-CD formed 1:1 and 1:2 inclusion complexes, but β-CD formed only a 1:1 inclusion complex. In the presence of drug, the interaction between CDs and HTAB decreased, because both drug and HTAB could interact with CDs. The results showed that the interaction between drug and CDs are greater than HTAB and CDs. The stoichiometry of the inclusion complexes, the critical aggregation concentration (CAC), the monomer surfactant concentration of HTAB, [HTAB]f, and also the effect of the inclusion complex on the micellization process of the HTAB were determined by conductivity measurements. 相似文献
39.
In the present paper, we study Casimir effect for a conformally coupled scalar field propagating on background of \(4+1\)-dimensional de Sitter (dS) space-time. The field is supposed to obey Dirichlet boundary condition on two 4-dimensional curved boundaries. Technically, we accomplish our calculations using an indefinite field quantization scheme, which already has been successfully applied to the dS minimally coupled massless scalar field and the dS linear gravity to obtain a causal and fully covariant quantum field on dS space-time. 相似文献
40.
Maryam Mirza‐Aghayan Rabah Boukherroub Mahshid Rahimifard Mohammad Bolourtchian 《应用有机金属化学》2010,24(6):477-480
Reduction of a variety of nitroaromatic compounds with triethylsilane in the presence of catalytic amounts of palladium chloride in ethanol resulted in the formation of the corresponding anilines in excellent yields. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献