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1.
Glass-based materials are usually considered as excellent seals for jointing adjacent components in planar solid oxide fuel cells, but the uncontrollable crystallization in the glass may cause delamination and micro-cracks in such seals. To solve this problem, Al2O3 ceramic particles were added to a BaO–CaO–Al2O3–B2O3–SiO2 glass system to reduce negative effects caused by crystalline phase on the gas tightness and the joint strength in the seals. At an operating temperature of 750 °C, the glass-based seals with 20 wt% Al2O3 addition (GA80) exhibited extremely low leakage rates (~0.002 sccm/cm under an input gas pressure of 13.6 kPa) and higher shear strength (3.31 MPa). The Al2O3 ceramic addition and the crystalline phase BaAl2Si2O8 reinforced the glass matrix. Further thermal cycle analyses indicated that leakage rates for the GA80 seals remained at around 0.0025 sccm/cm after 10 thermal cycles, which was consistent with minor microstructural change and good interface bonding. Single cell testing with of GA80 seals was performed and the results demonstrated stable electrochemical performance through 6 thermal cycles at an open circuit voltage of 1.16–1.18 V, as well as a power density above 546 mW/cm2 at a current density of 925 mA/cm2. These results showed the high thermal cycle stability of the glass/Al2O3 composite seals in intermediate temperature planar solid oxide fuel cells. 相似文献
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Liangyou Lin Timothy W. Jones Terry Chien-Jen Yang Noel W. Duffy Jinhua Li Li Zhao Bo Chi Xianbao Wang Gregory J. Wilson 《Advanced functional materials》2021,31(5):2008300
In the past decade, the perovskite solar cell (PSC) has attracted tremendous attention thanks to the substantial efforts in improving the power conversion efficiency from 3.8% to 25.5% for single-junction devices and even perovskite-silicon tandems have reached 29.15%. This is a result of improvement in composition, solvent, interface, and dimensionality engineering. Furthermore, the long-term stability of PSCs has also been significantly improved. Such rapid developments have made PSCs a competitive candidate for next-generation photovoltaics. The electron transport layer (ETL) is one of the most important functional layers in PSCs, due to its crucial role in contributing to the overall performance of devices. This review provides an up-to-date summary of the developments in inorganic electron transport materials (ETMs) for PSCs. The three most prevalent inorganic ETMs (TiO2, SnO2, and ZnO) are examined with a focus on the effects of synthesis and preparation methods, as well as an introduction to their application in tandem devices. The emerging trends in inorganic ETMs used for PSC research are also reviewed. Finally, strategies to optimize the performance of ETL in PSCs, effects the ETL has on J–V hysteresis phenomenon and long-term stability with an outlook on current challenges and further development are discussed. 相似文献
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Graphene and its derivatives have been considered intensively in the development and application of new types of adsorption and separation functional materials, due to its unique structure and superior performance. A comprehensive review on recent studies on adsorption and separation functional materials is given, including graphene, graphene oxide, graphene gel, graphene‐based sponge, graphene separation membrane as well as graphene continuous oil absorption and separation materials. Moreover, the preparation methods and application prospects are mainly utilized to illustrate the research progress. Especially, it is predicted that layered graphene membrane and graphene continuous oil absorption and separation materials may be the most research worthy. 相似文献
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Efficient energy and temperature management techniques are essential elements for operators of cloud data centers. Dynamic virtual machine (VM) consolidation using live migration techniques presents a great opportunity for cloud service providers to adaptively reduce energy consumption and optimize their resource utilization. In recent studies, power consumption readings of individual physical hosts were chosen as the main monitoring parameters in their allocation policies, whereas very few have considered host temperature, which has shown to have a negative impact on server reliability, as a migration criterion. In this work, a thermal-aware VM consolidation mechanism is proposed for resource allocation optimization and server reliability assurance. We consider the variability in host temperature as a migration criterion to avoid outage incidents via having better VM consolidations. Extensive simulation results obtained from CloudSim show the promising performance of the proposed mechanism in energy saving while reducing the number of server outage incidents due to fluctuations in host temperature. 相似文献
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针对传统采空区探测依靠全站仪测量存在劳动强度大、测量结果不准确等问题,采用BLSS-PE矿用三维激光扫描系统对罗河铁矿45-3^#和47-3^#采空区进行了现场扫描,构建了采空区三维实体模型,并在此基础上计算了采空区体积,说明了传统统计方式存在的不足;计算了矿房的超欠挖体积,为准确量化矿房损失率和贫化率提供了基础数据;基于采空区边界进行了二步骤回采设计,说明了采空区边界对于降低矿房损失贫化的重要意义。 相似文献
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World Wide Web - To solve the problem that users’ retrieval intentions are seldom considered by personalized websites, we propose an improved incremental collaborative filtering (CF)-based... 相似文献