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991.
992.
Hadi Hamid Shamlouei Hamid Reza 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(5-6):557-568
Journal of Inclusion Phenomena and Macrocyclic Chemistry - In this study, based on BODIPY molecule, new calix-like structures with significant electrical and optical properties were designed. These... 相似文献
993.
This paper proposes an efficient learning based approach to detect the faults of an industrial oil pump. The proposed method uses the wavelet transform and genetic algorithm (GA) ensemble for an optimal feature extraction procedure. Optimal features, which are dominated through this method, can remarkably represent the mechanical faults in the damaged machine. For the aim of condition monitoring, we considered five common types of malfunctions such as casing distortion, cavitation, looseness, misalignment, and unbalanced mass that occur during the machine operation. The proposed technique can determine optimal wavelet parameters and suitable statistical functions to exploit excellent features via an appropriate distance criterion function. Moreover, our optimization algorithm chooses the most appropriate feature submatrix to improve the final accuracy in an iterative method. As a case study, the proposed algorithms are applied to experimental data gathered from an industrial heavy-duty oil pump installed in Arak Oil Refinery Company. The experimental results are very promising. 相似文献
994.
Baharak Bahramnezhad Dadkhoda Ghazanfari Enayatollah Sheikhhosseini Mohammad Reza Akhgar Sayed Ali Ahmadi 《Journal of heterocyclic chemistry》2020,57(1):173-181
In this work, MnSb2O6-chitosan nanocomposites were synthesized and have been employed in Pechmann condensation for the synthesis of coumarin derivatives. MnSb2O6-chitosan nanocomposites were characterized by Fourier transform infrared (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX) techniques. The particles of MnSb2O6-chitosan have uniform spheres with sizes that are less than 100 nm. Simplicity, easy work-up, and short reaction times are advantages of this reaction. Also, we evaluated the antibacterial activity for some of the products, and the result showed significant pharmaceutical activities as antibacterial reagents against Staphylococcus aureus and Escherichia coli. 相似文献
995.
Research on Chemical Intermediates - Nano-Fe3O4@SiO2-3,4-dihydroxybenzaldehyde/barbituric acid/phthalhydrazide-FeCl3 (nano-Fe3O4@SiO2-HBP-FeCl3) was prepared and authenticated by usual analytical... 相似文献
996.
Maithani Rajesh Kumar Anil Gholamali Zadeh Peyman Safaei Mohammad Reza Gholamalizadeh Ehsan 《Journal of Thermal Analysis and Calorimetry》2020,139(2):1195-1212
Journal of Thermal Analysis and Calorimetry - A study was conducted to enhance the thermo-hydraulic performance of a rectangular solar air passage with integrated spherical-shaped turbulence... 相似文献
997.
Sheykhi Mohammad Reza Afrand Masoud Toghraie Davood Talebizadehsardari Pouyan 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2859-2880
Journal of Thermal Analysis and Calorimetry - In this paper, the effect of changing tube slope on the critical heat flux for the evaporation of upward saturated flow of a liquid (water) in a... 相似文献
998.
Reza Ahm Mohsinul Tavakoli Javad Zhou Yabin Qin Jianguang Tang Youhong 《中国科学:化学(英文版)》2020,63(3):308-324
Lipid bodies are dynamic organelles of photosynthetic microalgae that can be used as the third generation resources for biofuel production.Biosynthesis of lipids can be influenced by different signalling processes.Visualisation of these processes can provide useful information about the fate and associated roles of lipid molecules in different biological systems.In photosynthetic organisms,however,studies of calcium ediated lipid biosynthesis is bottlenecked due to the limitation of proper and efficient technologies,which also include visualisation techniques.Currently,most studies to visualise lipid droplets in vivo have used traditional dyes,and proper visualisation of lipid drops is hindered by dye-specific limitations.This hurdle could be overcome by using recently developed aggregation-induced emission biooprobes.This review reveals current knowledge gaps in the studies of lipid drops and calcium ions in microalgae,as calcium signaling is important secondary messenger to detect a wide variety of environmental stimuli in plant and animal cells.To obtain insight into the mechanisms of these processes,the merits and demerits of currently available visualisation techniques for lipid drops and calcium are also detailed.Finally,opportunities and possibilities are proposed to recommend further improvement of techniques for detecting the role of calcium during lipid formation in microalgae for biofuel production. 相似文献
999.
1000.
Employing the conventional quadratic norm to regularize the inverse problem in electrical impedance tomography often stabilizes the solution at the expense of imposing some smoothness on the reconstructed image. This study proposes a novel multi-regularized approach in order for quadratic norm regularization to reduce its deleterious effects on the reconstructed image. The amounts of regularization exerted on the finite elements over the mesh are not kept constant, but are changed depending on either the sensitivity of the boundary measurements to the finite elements, or the anomaly positioning. The results show that the proposed schemes appreciably improve the image with regard to spatial resolution, artifact, and shape preservation. These schemes considerably reduce the unappealing sensitivity of the inverse solution to the regularization parameter changes as well. 相似文献