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Babae Robabeh Ghezelbash Mahsa Majd Abdollah Eslami Darbani Seyyed Mohammad Reza 《Journal of Russian Laser Research》2022,43(2):162-168
Journal of Russian Laser Research - In this paper, we use laser-induced breakdown spectroscopy (LIBS) to investigate the laser-induced copper plasma with and without an external magnetic field,... 相似文献
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Sadeghi-Zadeh Mohammad Sadegh Khorrampanah Mahsa Houshmand Monireh Aghababa Hossein Mafi Yousef 《International Journal of Theoretical Physics》2021,60(10):3744-3759
International Journal of Theoretical Physics - The proposed quantum secret sharing protocol in this article conveys n bit secret messages from the sender to the n receivers making use of a secure... 相似文献
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Omid Bagheri Faranak Sadegh Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor‐Baltork Mahsa Safiri 《应用有机金属化学》2014,28(5):337-346
The tetrakis(4‐N‐methylpyridinium)porphyrinatopalladium(II) iodide, [Pd(TMPyP)]I4, supported on Dowex 50WX8 and Amberlite IR‐120 ion‐exchange resins, was used as heterogeneous, recyclable and active catalyst for the Suzuki–Miyaura and Heck cross‐coupling reactions. These catalysts were applied to coupling of various aryl halides with phenylboronic acid and styrene in Suzuki and Heck reactions, respectively, and the corresponding products were obtained in excellent yields and short reaction times. The catalysts could be recovered easily by simple filtration and reused several times without significant loss of their catalytic activity. The catalysts were characterized by diffuse‐reflectance UV–visible spectroscopy and scanning electron microscopy, and their stability was confirmed by TGA. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Omid Bozorg Haddad Mahsa Mirmomeni Mahboubeh Zarezadeh Mehrizi Miguel A. Mariño 《Computational Optimization and Applications》2010,47(1):97-128
Effective project management requires the development of a realistic plan and a clear communication of the plan from the beginning
to the end of the project. The critical path method (CPM) of scheduling is the fundamental tool used to develop and interconnect
project plans. Ensuring the integrity and transparency of those schedules is paramount for project success. The complex and
discrete nature of the solution domain for such problems causes failing of traditional and gradient-based methods in finding
the optimal or even feasible solution in some cases. The difficulties encountered in scheduling construction projects with
resource constraints are highlighted by means of a simplified bridge construction problem and a basic masonry construction
problem. The honey-bee mating optimization (HBMO) algorithm has been previously adopted to solve mathematical and engineering
problems and has proven to be efficient for searching optimal solutions in large-problem domains. This paper presents the
HBMO algorithm for scheduling projects with both constrained and unconstrained resources. Results show that the HBMO algorithm
is applicable to projects with or without resource constraints. Furthermore, results obtained are promising and compare well
with those of well-known heuristic approaches and gradient-based methods. 相似文献
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Mahsa Fatehi Mahmood Haji Shaabani Derek Thompson 《Complex Analysis and Operator Theory》2018,12(7):1767-1778
In this paper, we study quasinormal and hyponormal composition operators \(W_{\psi ,\varphi }\) with linear fractional compositional symbol \(\varphi \) on the Hardy and weighted Bergman spaces. We characterize the quasinormal composition operators induced on \(H^{2}\) and \(A_{\alpha }^{2}\) by these maps and many such weighted composition operators, showing that they are necessarily normal in all known cases. We eliminate several possibilities for hyponormal weighted composition operators but also give new examples of hyponormal weighted composition operators on \(H^2\) which are not quasinormal. 相似文献
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Mehrazar Mehrdad Hassankalhori Mahdi Toolabi Mahsa Goli Fereshteh Moghimi Setareh Nadri Hamid Bukhari Syed Nasir Abbas Firoozpour Loghman Foroumadi Alireza 《Molecular diversity》2020,24(4):997-1013
Molecular Diversity - A new series of compounds based on benzodiazepine-1,2,3-triazole were synthesized and evaluated as cholinesterase inhibitors by Ellman’s method. The compounds proved to... 相似文献
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Single and binary catalyst systems based on nickel and palladium in polymerization of ethylene 下载免费PDF全文
The catalyst (N,N‐bis(2,6‐dibenzhydryl‐4‐ethoxyphenyl)butane‐2,3‐diimine)nickel dibromide, a late transition metal catalyst, was prepared and used in ethylene polymerization. The effects of reaction parameters such as polymerization temperature, co‐catalyst to catalyst molar ratio and monomer pressure on the polymerization were investigated. The α‐diimine nickel‐based catalyst was demonstrated to be thermally robust at a temperature as high as 90 °C. The highest activity of the catalyst (494 kg polyethylene (mol cat)?1 h?1) was obtained at [Al]/[Ni] = 600:1, temperature of 90 °C and pressure of 5 bar. In addition, the performance of a binary catalyst using nickel‐ and palladium‐based complexes was compared with that of the corresponding individual catalytic systems in ethylene polymerization. In a study of the catalyst systems, the average molecular weight and molecular weight distribution for the binary polymerization were between those for the individual catalytic polymerizations; however, the binary catalyst activity was lower than that of the two individual ones. The obtained polyethylenes had high molecular weights in the region of 105 g mol?1. Gel permeation chromatography analysis showed a narrow molecular weight distribution of 1.44 for the nickel‐based catalyst and 1.61 for the binary catalyst system. The branching density of the polyethylenes generated using the binary catalytic system (30 branches/1000 C) was lower than that generated using the nickel‐based catalyst (51/1000 C). X‐ray diffraction study of the polymer chains showed higher crystallinity with lower branching of the polymer obtained. Also Fourier transform infrared spectra confirmed that all obtained polymers were low‐density polyethylene. 相似文献