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131.
A mixed CuI/CuIIcatalyst based on magnetic cysteine functionalized graphene oxide (CuI/II@Cys-MGO) was prepared and used for the azidonation reaction of aryl boronic acids and one-pot synthesis of 1,4-diaryl −1,2,3-triazoles. Aryl azides were obtained in good yields and short reaction times via cross-coupling of aryl boronic acids with sodium azide in the presence of CuII catalytic species in this catalytic system. The azide-alkyne cycloaddition reaction was catalyzed by CuI catalytic species in CuI/II@Cys-MGO nanocomposite. 相似文献
132.
Fatemeh Jafari Mehmandoost-Khajeh-Dad Ali Akbar Mohammadi-Dadkan Maysam Ghal-Eh Nima Yazdandoust Hamideh 《Physics of Particles and Nuclei Letters》2019,16(6):761-767
Physics of Particles and Nuclei Letters - Plastic scintillators are widely used in detecting nuclear radiation due to their low construction cost, the ability to be produced in nearly any shape and... 相似文献
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Neshat Askarzadeh Masoumeh Haghbin Nazarpak Korosh Mansoori Mehdi Farokhi Mahdi Gholami Javad Mohammadi Fatemeh Mottaghitalab 《Macromolecular bioscience》2020,20(9)
Herein, a bilayer cylindrical conduit (P‐CA) is presented consisting of electrospun polycaprolactone (PCL) nanofibers and sodium alginate hydrogel covalently cross‐linked with N,N′‐disuccinimidyl carbonate (DSC). The bilayer P‐CA conduit is developed by combining the electrospinning and outer–inner layer methods. Using DSC, as a covalent crosslinker, increases the degradation time of the sodium alginate hydrogel up to 2 months. The swelling ratio of the hydrogel is also 503% during the first 8 h. The DSC cross‐linked sodium alginate in the inner layer of the conduit promotes the adhesion and proliferation of nerve cells, while the electrospun PCL nanofibers in the outer layer provide maximum tensile strength of the conduit during surgery. P‐CA conduit promotes the migration of Schwann cells along the axon in a rat model based on functional and histological evidences. In conclusion, P‐CA conduit will be a promising construct for repairing sciatic nerves in a rat model. 相似文献
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Seyyed Javad Sabounchei Khadijeh Badpa Mehdi Bayat Roya Karamian Fatemeh Ghasemlou Robert W. Gable Parviz Gohari Derakhshandeh Kristof Van Hecke 《应用有机金属化学》2019,33(3)
The reaction of α‐keto‐stabilized diphosphine ylides [Ph2P(CH2)nPPh2═C(H)C(O)C6H4‐p‐CN] (n = 1 (Y1); n = 2 (Y2)) with dibromo(1,5‐cyclooctadiene) palladium(II)/platinum(II) complexes, [Pd/PtBr2(cod)], in equimolar ratio gave the new cyclometalated Pd(II) and Pt(II) complexes [Br2Pd(κ2‐Y1)] ( 1 ), [Br2Pt(κ2‐Y1)] ( 2 ), [Br2Pd(κ2‐Y2)] ( 3 ) and [Br2Pt(κ2‐Y2)] ( 4 ). These compounds were screened in a search for novel antibacterial agents and characterized successfully using Fourier transfer infrared and NMR (1H, 13C and 31P) spectroscopic methods. Also, the structures of complexes 1 and 2 were characterized using X‐ray crystallography. The results showed that the P,C‐chelated complexes 1 and 2 have structures consisting of five‐membered rings, while 3 and 4 have six‐membered rings, formed by coordination of the ligand through the phosphine group and the ylidic carbon atom to the metal centre. Also, a theoretical study of the structures of complexes 1 – 4 was conducted at the BP86/def2‐SVP level of theory. The nature of metal–ligand bonds in the complexes was investigated using energy decomposition analyses (EDA) and extended transition state combined with natural orbitals for chemical valence analyses. The results of EDA confirmed that the main portions of ΔEint, about 57–58%, in the complexes are allocated to ΔEelstat. 相似文献
137.
Dr. Thomas G. McKenzie Fatemeh Karimi Prof. Muthupandian Ashokkumar Prof. Greg G. Qiao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(21):5372-5388
The use of ultrasound as an external stimulus for promoting polymerization reactions has received increasing attention in recent years. In this Review article, the fundamental processes that can lead to either the homolytic cleavage of polymer chains, or the sonolysis of solvent (or other) small molecules, under the application of ultrasound are described. These reactions promote the production of reactive radicals, which can be utilized in chain-growth radical polymerizations under the right conditions. A full historical overview of the development of ultrasound-assisted radical polymerization is provided, with special attention given to the recently described systems that are “controlled” by methods of reversible (radical) deactivation. Perspectives are shared on what challenges still remain in polymer sonochemistry, as well as new areas that are yet to be explored. 相似文献
138.
Synthesis of 5‐substituted 1H‐tetrazoles using a recyclable heterogeneous nanonickel ferrite catalyst
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An efficient method was developed for the [2 + 3] cycloaddition of sodium azide with nitriles to afford 5‐substituted 1H‐tetrazoles using nanonickel ferrite (NiFe2O4) as an effective heterogeneous catalyst in dimethylformamide. The main advantages of this method are high yields, simple methodology and easy work‐up. The catalyst can be recovered and reused for several cycles with predictable activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
139.
Goudarziafshar Hamid Moosavi-Zare Ahmad Reza Hosseinabadi Fatemeh Jalilian Zahra 《Research on Chemical Intermediates》2022,48(4):1423-1437
Research on Chemical Intermediates - Nano-Mn-[phenyl-salicylaldimine-methyl-pyranopyrimidinedione]Cl2 {Nano-[Mn-PSMP]Cl2} as a new Schiff base complex was prepared and characterized by various... 相似文献
140.