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991.
Telecommunication Systems - Broadcast storm refers to the bandwidth saturation caused by broadcast traffic flows when a loop exists and it can quickly lead to the network failure. In legacy... 相似文献
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Ebrahimi Bavili Robab Akbari Ahmad Mahboobi Esfanjani Reza 《Intelligent Service Robotics》2020,13(3):419-437
Intelligent Service Robotics - This paper addresses the problem of asymptotic stability and position tracking in nonlinear teleoperation systems interacting with non-passive operator and... 相似文献
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Behzad Shirkavand Hadavand Maryam Jouyandeh Seyed Mohamad Reza Paran Reza Khalili Henri Vahabi Hamed Fakharizadeh Bafghi Fouad Laoutid P. Poornima Vijayan Mohammad Reza Saeb 《应用聚合物科学杂志》2020,137(45):49412
This work reports on nonisothermal degradation kinetics of polyurethane (PU)-based powder coatings containing 1, 3, and 5%wt% vinyltrimethoxysilane functionalized Al2O3 (V-Al2O3) nanoparticles. Thermogravimetric analysis of PU/V-Al2O3 powder coatings with different V-Al2O3 contents has been performed at different heating rates. Variation of activation energy (Ea) of PU/V-Al2O3 powder coatings was modeled as a function of partial mass loss by using Kissinger–Akahira–Sunose, Ozawa–Wall–Flynn and modified Coats–Redfern isoconversional approaches. The results revealed hindered decomposition process of PU/V-Al2O3 nanocomposite powder coatings, featured by an increase in activation energy of degradation from ∼158 for blank PU to 225, 183, and 229 kJ/mol for nanocomposites filled with 1, 3, and 5 wt% of V-Al2O3, respectively. Likewise, pre-exponential factor values increased for samples containing V-Al2O3 nanoparticles compared to that of blank sample. Sestak–Berggren kinetic model appropriately captured thermal degradation behavior of PU/V-Al2O3 nanocomposites than that of nth order decomposition kinetic reaction models. 相似文献
995.
Dr. Rosa Purgatorio Dr. Larisa N. Kulikova Dr. Leonardo Pisani Dr. Marco Catto Dr. Modesto de Candia Prof. Antonio Carrieri Prof. Saverio Cellamare Dr. Annalisa De Palma Andrey A. Beloglazkin Ghulam Reza Raesi Prof. Leonid G. Voskressensky Prof. Cosimo D. Altomare 《ChemMedChem》2020,15(20):1947-1955
A number of 1,2,3,4-tetrahydrochromeno[3,2-c]pyridin-10-one derivatives have been synthesized and screened against different targets involved in the onset and progression of Alzheimer's disease (AD), such as acetyl- and butyrylcholinesterase (AChE and BChE), monoamine oxidases A and B (MAO A and B), aggregation of β-amyloid (Aβ) and reactive oxygen species (ROS) production. Derivatives 1 c , 3 b , 4 and 5 a showed multifaceted profiles of promising anti-AD features and returned well-balanced multitargeting inhibitory activities. Moreover, compound 1 f , a potent and selective human MAO B inhibitor (IC50=0.89 μM), proved to be a safe neuroprotectant in a human neuroblastoma cell line (SH-SY5Y) by improving viability impaired by Aβ1–42 and pro-oxidant insult. Furthermore, structure–activity relationships (SARs) and docking models were derived in order to assist further hit-to-lead optimization stage. 相似文献
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Sadegh Azizi Darsara Majid Seifi Mohammad Bagher Askari Mohammad Osquian 《Ceramics International》2021,47(15):20992-20998
In this research, Ni3S4–NiS with starfish morphology was synthesized with a simple hydrothermal method and then hybridized with reduced graphene oxide (rGO) as a material for high-performance supercapacitors. The crystal structure and morphology of the as-prepared materials were studied by X-ray diffraction spectroscopy and electron microscopy. Uniform distribution of Ni3S4–NiS on rGO was observed from electron microscopy images. The results showed that Ni3S4–NiS/rGO with a specific capacitance of 1578 Fg-1 and discharge time of 603 s at the current density of 0.5 Ag-1 has more capacity and stability relative to Ni3S4–NiS. The cyclic stability after 5000 cycles showed that the Ni3S4–NiS/rGO electrode is stable, and 91% of its corresponding initial capacitance retained at the end of 5000 cycles. The good results in capacitance and stability of this electrode can be regarded as an improvement for the development of highly efficient and economic supercapacitors for portable electronic devices. 相似文献
1000.
Nitrile‐based nanocomposite heat insulators are very attractive materials compared with their similar nonelastomeric counterparts, due to their higher deformation bearing capacity in special applications. Modeling of these ablative nanocomposites enables us to determine the exact required thickness of the insulator and temperature distribution across it at predetermined thermal conditions. The complete form of the ablation equation is a transient nonlinear second‐order differential equation with variable temperature‐dependent thermo‐physical properties, which must be determined during thermal degradation. In this work, in addition to experimental investigation of ablative elastomeric nanocomposites based on NBR, the ablation process is modeled analytically with perturbation theory in the Lagrangian coordinate system because of surface recession and moving boundaries. Kirchhoff transformation was used to get rid of the temperature dependence of k in each zonal of virgin and char. The theoretical results were confirmed by experimental data obtained from the oxyacetylene flame test. The results proposed a competitive nitrile‐based nanocomposite heat insulator with superior ablation properties: mass ablation rate 0.014 g s?1, linear ablation rate 0.012 mm s?1, and insulating index number 6800 s m?1, under a standard test with a heat flux of 2500 kW m?2 for 15 seconds. 相似文献