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71.
A. Jannifar M. N. M. Zubir S. N. Kazi N. W. M. Zulkifli N. Ahmad 《Journal of Mechanical Science and Technology》2018,32(7):3009-3021
This study focuses on introducing a criteria for conducting harmonic excitation signal elimination as well as investigating its effectiveness towards achieving complete isolation of harmonic disturbance in performing EMA under operational condition. By modulating the ratio between harmonic excitation and impact knocking frequencies, it was revealed that the harmonic signal was efficiently attenuated with sufficient number of averaging blocks. The results highlighted close agreement between simulation and experimental approaches with maximum deviation of 2 %, under specific design criteria. It was determined that a non-periodic triggering frequency significantly affect the elimination performance in terms of trend and amplitude reduction. This work underlines the importance of controlling the triggering frequency to yield the desired design criteria for achieving rapid and highly efficient elimination of harmonic excitation signal. The results have proven that the proposed technique can be further adapted to isolate the harmonic in conventional EMA conducted under operational condition. 相似文献
72.
Pukkalanun T. Moonmuang P. Tangsrirat W. 《Journal of Communications Technology and Electronics》2021,66(4):439-450
Journal of Communications Technology and Electronics - Alternative circuit designs concerning the simulation of floating lossy inductors using voltage differencing buffered amplifiers (VDBAs) are... 相似文献
73.
The present work provides an evaluation of the thermodynamic calculation, using the FactSage software, which allows the study of the interaction of a system of various oxides. It started with the examination of the crystalline phases present in the raw materials indicated by the FactSage and compared with the analysis by XRD. Subsequently, the crystalline phases and the amount of liquid phase predicted by the software at different firing temperatures were analyzed. These results were compared with experimental data and records from the literature. The FactSage showed consistent results, managing to indicate the presence of the main phases in the raw materials; however, the actual and predicted secondary phases did not always coincide. The type of phase in the firing was correctly indicated, tridymite (stable phase above 867 °C), mullite and liquid phase, but their quantity in relation to the firing temperature was quite different from the experimental data. 相似文献
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76.
Hyun Suk Lim Minbeom Lee Yikyeom Kim Dohyung Kang Jae W. Lee 《International Journal of Hydrogen Energy》2021,46(29):15497-15506
This work introduces LaCo1-xNixO3 (x = 0, 0.1, 0.25, and 0.4) perovskite catalysts for enhancing the low temperature performance of reverse water-gas shift (RWGS) reaction. Incorporating Ni lowers the interaction between La-site and B-site, weakening the electron donation from La-site to B-site. The B-site elements with the weak interaction can be easily diffused from the bulk to form exsolved bimetallic Co–Ni alloy on the surface. This different interaction trends further control H2 dissociation activity and CO desorption that affect CO2 conversion and CO selectivity, respectively. While the Ni-incorporated catalyst shows a higher metal dispersion to enhance H2 dissociation activity and increases CO2 conversion, the La-sites with the weak electron donation further drive the strong adsorption of CO molecules to be additionally hydrogenated, eventually lower CO selectivity. However, incorporating 10 at% Ni into the B site of LaCoO3 (LaCo0.9Ni0.1O3) achieved a balanced effect between facile H2 dissociation and CO desorption to maximize RWGS activity. The LaCo0.9Ni0.1O3 catalyst displayed outstanding activity with an average CO2 conversion of 30.8%, which is close to the equilibrium conversion, and a CO selectivity of 98.8% at 475 °C over 50 h. 相似文献
77.
Fabien Paulot David Paynter Vaishali Naik Sergey Malyshev Raymond Menzel Larry W. Horowitz 《International Journal of Hydrogen Energy》2021,46(24):13446-13460
Hydrogen (H2) has been proposed as an alternative energy carrier to reduce the carbon footprint and associated radiative forcing of the current energy system. Here, we describe the representation of H2 in the GFDL-AM4.1 model including updated emission inventories and improved representation of H2 soil removal, the dominant sink of H2. The model best captures the overall distribution of surface H2, including regional contrasts between climate zones, when vd(H2) is modulated by soil moisture, temperature, and soil carbon content. We estimate that the soil removal of H2 increases with warming (2–4% per K), with large uncertainties stemming from different regional response of soil moisture and soil carbon. We estimate that H2 causes an indirect radiative forcing of 0.84 mW m?2/(Tg(H2)yr?1) or 0.13 mW m?2 ppbv?1, primarily due to increasing CH4 lifetime and stratospheric water vapor production. 相似文献
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Ke Dong Warnakulasuriya M. A. D. Binosha Fernando Rosalie Durham Regine Stockmann Dona Pamoda W. Jayatunga Vijay Jayasena 《International Journal of Food Science & Technology》2020,55(9):3073-3081
Evidence suggests that diets rich in antioxidants reduce the risk factors of Alzheimer’s disease (AD). Hippophae rhamnoides, commonly known as sea buckthorn (SB), is rich in antioxidants which could have direct effects on amyloid-beta (Aβ) levels and consequently influence AD pathogenesis. In this study, sea buckthorn powder (SBP) was administered at varying concentrations (0.6, 0.9, 1.2, 1.5 and 1.8 µg mL−1) to cell cultures (BE(2)-M17) with 20 mm Aβ for 72 h. MTS test indicated that SB significantly increased cell viability in Aβ-induced cells up to 95%. Results of Western blot showed maximum 38% inhibition of Aβ compared to the control (Aβ only). ELISA demonstrated significantly lower amyloid-β level (6672 pg mL−1) than the control (10189 pg mL−1). Images of AFM further confirmed the presence of low quantity of amyloid beta in SBP-treated cells. These findings suggest that SB warrants further investigation as potential therapeutic agent in the treatment of AD. 相似文献
80.
We show that in the presence of magnetic field, two superconducting phases with the center-of-mass momentum of Cooper pair parallel to the magnetic field are induced in Dresselhaus spin–orbit-coupled superconductor. Specifically, at small magnetic field, the center-of-mass momentum is induced due to the energy-spectrum distortion and no unpairing region with vanishing singlet correlation appears. We refer to this superconducting state as the drift-BCS state. By further increasing the magnetic field, the superconducting state falls into the Fulde–Ferrell state with the emergence of the unpairing regions. The observed abrupt enhancement of the center-of-mass momenta and suppression on the order parameters during the transition indicate the occurrence of a first-order phase transition. Enhanced Pauli limit and hence enlarged magnetic-field regime of the Fulde–Ferrell state, due to the spin-flip terms of the spin–orbit coupling, are revealed. We also address the triplet correlations induced by the spin–orbit coupling, and show that the Cooper-pair spin polarizations, generated by the magnetic field and center-of-mass momentum with the triplet correlations exhibit totally different magnetic-field dependences between the drift-BCS and Fulde–Ferrell states. 相似文献