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排序方式: 共有2719条查询结果,搜索用时 15 毫秒
1.
Wireless Networks - Beyond five generation (B5G) systems will demand strict and heterogeneous service requirements for the emerging applications. One solution to meet these demands is the dense... 相似文献
2.
Luna-Morales María Elena Luna-Morales Evelia Flores-Vargas Xochitl Valencia-Martinez Andrea Collazo-Reyes Francisco Perez-Angon Miguel Ángel 《Scientometrics》2022,127(1):661-681
Scientometrics - Consolidation of the scientific activity in Latin American research centers has been a matter of serious concern in recent years. In the present study we use a data set of the WoS... 相似文献
3.
Mechanical properties and thermal shock in thin ZrO2–Y2O3–Al2O3 films obtained by the sol-gel method
Antonio Díaz-Parralejo M. Ángeles Díaz-Díez José Sánchez-González Antonio Macías-García Juan Pablo Carrasco-Amador 《Ceramics International》2021,47(1):80-86
Thin multilayer coatings of ZrO2–Y2O3–Al2O3 were prepared using the sol-gel method and dip-coating technique in order to advance in the study of what influence the incorporation of Al2O3 has on films of Y2O3-doped ZrO2, investigating its role in the synthesis of the solutions and in the characteristics and properties of the coatings. After the characterization of the solutions used in the process, the microstructure of the films was studied and their mechanical behaviour and resistance to thermal shock were determined so as to optimize the characteristics and functionality of these coatings. With increased alumina content, 3YSZ-Al2O3 (20 mol%), the cubic phase of the zirconia disappeared completely at the sintering temperature used (700 °C), resulting in the tetragonal phase with Al in solution. There was also a decrease in the coatings' hardness and Young's modulus, and an increase in toughness and resistance to thermal shock. These results allow guidelines to be established for the design of multilayer structures that are, tougher, more resistant, and have improved surface properties. 相似文献
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5.
Gerardo Valadez Huerta Johanan Álvarez Jordán Michael Dragon Keno Leites Stephan Kabelac 《International Journal of Hydrogen Energy》2018,43(34):16684-16693
Solid oxide fuel cell (SOFC) systems with anode off-gas recirculation (AGR) and diesel pre-reforming are advantageous because they can operate with the current fuel infrastructure. In the SchIBZ-project, the prototype of such a SOFC system for maritime applications has already been commissioned. In this first paper, we model the system devices to conduct an exergy analysis of this real SOFC plant and validate them with experimental values from experiments in laboratory scale. The results of our simulation agree well with the experimental values. The calculations with the validated results may be closer to the real thermodynamic behavior of such system components than previous literature. 相似文献
6.
Concentration of Gamma‐Linolenic and Stearidonic Acids as Free Fatty Acids and Ethyl Esters from Viper's Bugloss Seed Oil by Urea Complexation 下载免费PDF全文
7.
Gastón Gutiérrez-Gamboa Eva P. Pérez-Álvarez Pilar Rubio-Bretón Teresa Garde-Cerdán 《International Journal of Food Science & Technology》2019,54(4):1160-1168
Edible mushrooms production presents a potential problem for the environment, due to the large amount of waste generated. These wastes contain nitrogenous matter, which could be used as biostimulant in plants. The aim of this work was to study the effect of waste waters, from the mushroom production process, applied at veraison and 1 week later to grapevine leaves, on grape volatile compounds over two vintages. The results evidenced that mushroom water treatment decreased the grape content of certain terpenoids, C13 norisoprenoids, benzenoid compounds and esters, increasing C6 compounds content during the first season. Treated mushroom water application slightly affected grape volatile composition. This was the treatment that least affected the content of grape volatile composition. Few differences were found after the biostimulation during the second vintage. The season was the dominant factor of grape volatile content variation compared to the treatment and their interaction. 相似文献
8.
Jaume Sastre‐Juan Jaume Valentines‐lvarez 《Centaurus; international magazine of the history of science and medicine》2019,61(1-2):2-13
How do nuclear technologies become commonplace? How have the borders between the exceptional and the banal been drawn and redrawn over the last 70 years in order to make nuclear energy part of everyday life? This special issue analyzes the role of fun and display, broadly construed, in shaping the cultural representation and the material circulation (or non‐circulation) of nuclear technologies. Four case studies, covering the United States, Great Britain, Portugal, Spain, and Ukraine from the 1950s to the 2000s, explore how specific forms of public display and playful practices of cultural production were used as means to banalize (or de‐banalize) nuclear energy. This introduction addresses the main theoretical and historiographical signposts of the special issue and outlines the different ways in which the articles explore them. 相似文献
9.
Alonso de Armiño Carlos Manzanedo Miguel Ángel Herrero Álvaro 《Pattern Analysis & Applications》2020,23(3):1059-1070
Pattern Analysis and Applications - As is widely acknowledged, the transportation of goods by road can, in one way or another, be linked to a range of macroeconomic indicators. A hybrid artificial... 相似文献