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Rodríguez-Pérez Ángel Mariano Pérez-Calañas Cinta Pulido-Calvo Inmaculada 《Water Resources Management》2021,35(6):1977-1990
Water Resources Management - This paper aims to evaluate the possibility of using non-utilized hydraulic energy in urban water distribution systems. For this purpose, the viability and possible... 相似文献
115.
D. Kherifi H. Belhouchet S. Ramesh K.Y. Sara Lee A. Kenzour S. Djoualah M.K.G. Abbas Y.H. Wong S. Ramesh 《Ceramics International》2021,47(12):16483-16490
In this work, the sintering behaviour of fluorapatite (FAp)–silicate composites prepared by mixing variable amounts of natural quartz (2.5 wt% to 20 wt%) and FAp was studied. The composites were pressureless sintered in air at temperatures from 1000 °C to 1350 °C. The effects of temperatures on the densification, phase formation, chemical bonding and Vickers hardness of the composites were evaluated. All the samples exhibited mixed phase, comprising FAp and francolite as the major constituents along with some minor phases of cristobalite, wollastonite, dicalcium silicate and/or whitlockite dependent on the quartz content and sintering temperature. The composite containing 2.5 wt% quartz exhibited the best sintering properties. The highest bulk density of 3 g/cm3 and a Vickers hardness of >4.2 GPa were obtained for the 2.5 wt% quartz–FAp composite when sintered at 1100 °C. The addition of quartz was found to alter the microstructure of the composites, where it exhibited a rod-like morphology when sintered at 1000 °C and a regular rounded grain structure when sintered at 1350 °C. A wetted grain surface was observed for composites containing high quartz content and was believed to be associated with a transient liquid phase sintering. 相似文献
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Wireless Personal Communications - Cloud computing is a growing technology where lot of heterogeneous resources are available and large amount of requests are submitted by the customers... 相似文献
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Upconversion phosphors are known as a material system that can convert near-infrared light into visible/ultraviolet emissions by sequentially absorbing multiple photons. The studies on upconversion materials often use two rare earth (RE) ions as a sensitizer-activator pair. We investigated the influences on luminescence intensity depending on Cr-doping content (x) of hexagonal NaLu0.98–xCrxF4Er0.02 (x = 0–0.9) upconversion material by substituting Lu3+ ions with Cr3+in the absence of Gd3+. The change in upconversion luminescence intensity appears with saddle-like shape. We suggest that Cr3+ ions play the dual role as a constituent in host lattice and a sensitizer in the upconversion process. Optimal conditions for gaining the strongest upconversion emission correspond to x = 0.3–0.5, where there are effective energy transfers between Cr3+ and Er3+ ions and CrEr dimers. Apart from these values, the emission intensity decreases rapidly which can be ascribed to the absence of multiple-photon absorption for the case of low Cr3+ contents, and to the coupling between Cr3+ and/or Er3+ ions for the case of high Cr3+ contents. Magnetization and electron-spin-resonant measurements were performed to understand the correlation between the optical and magnetic properties. 相似文献
118.
Influence of Wheel Blunting on the Machining Precision in CNC Plunge Grinding: Digital Twin Analysis
Akintseva A. V. Pereverzev P. P. Prokhorov A. V. Omel’chenko S. V. 《Russian Engineering Research》2022,42(7):726-730
Russian Engineering Research - The machining precision in grinding a flexible shaft by sharp and blunt wheels is compared for a CNC system with a specified cycle of radial supply velocities. To... 相似文献
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Kooij Julian F. P. Flohr Fabian Pool Ewoud A. I. Gavrila Dariu M. 《International Journal of Computer Vision》2019,127(3):239-262
International Journal of Computer Vision - Anticipating future situations from streaming sensor data is a key perception challenge for mobile robotics and automated vehicles. We address the problem... 相似文献