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51.
Samaneh Zarei Golzar Komeili Saeed Bahadorikhalili Azadeh Yahya-Meymandi Morteza Karami-Zarandi Bagher Larijani Mahmood Biglar Seyed Esmaeil Sadat Ebrahimi Mohammad Mahdavi 《Journal of heterocyclic chemistry》2020,57(12):4254-4261
In this paper, a novel series of 2-(4-((1-aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)2-(2-oxoazetidin-1-yl)acetamide derivatives are synthesized in two steps. The first step involved Ugi multicomponent reaction of β-alanine, o-(propargyl)benzaldehyde and isocyanide derivatives. The product of this step, underwent a click 1,3-dipolar cycloaddition reaction with benzyl azide derivatives. The 2-(4-((1-aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)2-(2-oxoazetidin-1-yl)acetamide product was characterized and their antibacterial activities were evaluated against various G-positive (Staphylococcus aureus and Bacillus subtilis) and G-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria, using minimal inhibition concentration. The compounds showed very good antimicrobial activity and a number of products have been more active than ciprofloxacin. 相似文献
52.
Anizadeh Mohammad Reza Zolfigol Mohammad Ali Yarie Meysam Torabi Morteza Azizian Saeid 《Research on Chemical Intermediates》2020,46(8):3945-3960
Research on Chemical Intermediates - In this paper, tributyl(carboxymethyl)phosphonium bromotrichloroferrate as a new magnetic ionic liquid bearing acetic acid tags was synthesized and... 相似文献
53.
Morteza Rezaei Talarposhti Tristan Asset Samuel T. Garcia Yechuan Chen Sergio Herrera Sheng Dai Eric J. Peterson Kateryna Artyushkova Iryna Zenyuk Plamen Atanassov 《Chemphyschem》2020,21(12):1331-1339
We investigated the oxygen reduction reaction (ORR) mechanism on Pt nanoparticles (NPs) dispersed on several carbon blacks with various physicochemical properties (i. e. specific surface ranging from 80 to 900 m2 g−1, different graphitization degree, etc.). Using the kinetic isotope effect (KIE) along with various electrochemical characterizations, we determined that the rate determining step (RDS) of the ORR is a proton-independent step when the density of Pt NPs on the surface of the carbon support is high. Upon decrease of the density of Pt NPs on the surface, the RDS of the ORR starts involving a proton, as denoted by an increase of the KIE >1. This underlined the critical role played by the carbon support in the oxygen reduction reaction electrocatalysis by Pt supported on high surface area carbon. 相似文献
54.
Meccanica - Passive micromixers, due to their relatively high mixing efficiency and simple fabrication, have wide applications in biological, medical, and chemical processes. Serpentine and... 相似文献
55.
56.
Morteza Yavari 《International Journal of Theoretical Physics》2009,48(11):3169-3172
In this paper, we show that how to apply the time dependent quasi-Maxwell equations for exact solution of Einstein field equations
in vacuum for Petrov type {3,1} metric. 相似文献
57.
Gh.R. Amiri M.H. YousefiS. Manouchehri M.H. KeshavarzS. Fatahian 《Journal of magnetism and magnetic materials》2011,323(6):730-734
In this work, Mn0.7Zn0.3Fe2O4 and Ni0.7Zn0.3Fe2O4 nanoparticles with super-paramagnetic properties and size distribution from 10 to 52 nm were investigated. These particles were produced by a low-temperature solid-state reaction method without the ball-milling process. The size and morphology of the nanocrystallites were determined by X-ray diffraction, transmission electron microscopy and scanning tunneling microscopy methods. Magnetic measurements such as alternating gradient field magnetometers were used to justify the super-paramagnetic properties of these nanoparticles. Their microwave absorption in the range of 8-18 GHz was studied by a vector network analyzer. Responses of the device under tests were studied. Also, the percentage of the resin, the size and thickness of the mount were determined. The band width of 2.3 GHz was obtained with reflection-loss/written-loss of −16 dB around 10.4 GHz. 相似文献
58.
Other Index
Key Word Index of Volume 36 – 2001 相似文献59.
Reza Pourgholi Amin Esfahani Morteza Abtahi 《Journal of Applied Mathematics and Computing》2013,41(1-2):61-79
In this paper, we will first study the existence and uniqueness of the solution of a two-dimensional inverse heat conduction problem (IHCP) which is severely ill-posed, i.e., the solution does not depend continuously on the data. We propose a stable numerical approach based on the finite-difference method and the least-squares scheme to solve this problem in the presence of noisy data. We prove the convergence of the numerical solution, then to regularize the resultant ill-conditioned linear system of equations, we apply the Tikhonov regularization 0th, 1st and 2nd method to obtain the stable numerical approximation to the solution. The stability and accuracy of the scheme presented is evaluated by comparison with the Singular Value Decomposition (SVD) method. 相似文献
60.
N. Azizi A. Khajeh Amiri M. Bolourtchian M. R. Saidi 《Journal of the Iranian Chemical Society》2009,6(4):749-753
An environmentally benign and efficient process for the preparation of thioethers was developed by simple and practical reactions of alkyl halides and thiols in water in the presence of K2CO3 or Et3N in very high yields. The reaction of aryl, alkyl, aliphatic and hindered thiols with various alkyl halides gave the corresponding products with significant advantages such as high conversions, short reaction time, mild reaction conditions, and low cost, simple workup with good to quantitative yields. 相似文献