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991.
Ning Han Junling Cheng Dezhi Han Guoliang Chen Shuguang Zhang Guangjian Wang Naitao Yang Shaomin Liu 《国际能源研究杂志》2019,43(14):8890-8897
Recently, the reported Perovskite/Ruddlesden‐Popper composite with significant improvement of oxygen surface kinetics has been adopted into gas separation process. Here, we report a novel La0.7Sr0.3FeO3 ? δ/(La0.5Sr0.5)2CoO4 + δ (LSF‐LSC) composite hollow fiber membrane (HFM), which was characterized by X‐ray diffraction (XRD), scanning electron microscope (SEM), and thermal expansion test, etc. The O2 permeation test results indicated that, under sweeping gas of pure He (100 mL min?1), the composite HFM exhibited the superior O2 permeability (0.72 mL min?1 cm?2) at the temperature of 950°C with respect to the single La0.7Sr0.3FeO3 ? δ (LSF) membrane, acid‐etched membrane, and (La0.5Sr0.5)2CoO4 + δ (LSC)‐coated membrane. Moreover, the composite membrane exhibited high CO2 tolerance as well as phase stability. The generation of hetero‐interface between Ruddlesden‐Popper phase and perovskite phase could be responsible for the improvement of the oxygen transportation over the fabricated composite membrane. 相似文献
992.
Photonic Network Communications - A low complexity carrier phase estimation (CPE) algorithm for M-ary quadrature amplitude modulation (m-QAM) optical communication systems is investigated in this... 相似文献
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996.
Wei Wang Qi Han Zhijia Zhu Lishan Zhang Shan Zhong Baojiang Liu 《Advanced Powder Technology》2019,30(9):1882-1896
Photocatalytic performance of four tetracycline antibiotics using BiVO4/TiO2/RGO composites was investigated. To make full use of catalysis, optimum preparation conditions involved RGO content, solution pH and hydrothermal temperature on the structure forming of BiVO4/TiO2/RGO composites were investigated. Subsequently, the obtained visible light-driven photocatalyst was used to degrade four kinds of tetracycline antibiotics involved tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) for wastewater treatment. Results showed that BiVO4/TiO2/RGO photocatalyst exhibited excellent photocatalytic activity and high compatibility due to the enhanced separation efficiency of photo-generated carriers with high reduction and oxidation capability. The degradation process of four kinds of tetracycline antibiotics was traced and detected through identifying intermediates produced in the reaction system. And a possible catalytic mechanism for BiVO4/TiO2/RGO photocatalyst was put forward based on band gap structure of BiVO4 and TiO2. 相似文献
997.
Won‐Gwang Lim Changshin Jo Ara Cho Jongkook Hwang Seongseop Kim Jeong Woo Han Jinwoo Lee 《Advanced materials (Deerfield Beach, Fla.)》2019,31(3)
Porous architectures are important in determining the performance of lithium–sulfur batteries (LSBs). Among them, multiscale porous architecutures are highly desired to tackle the limitations of single‐sized porous architectures, and to combine the advantages of different pore scales. Although a few carbonaceous materials with multiscale porosity are employed in LSBs, their nonpolar surface properties cause the severe dissolution of lithium polysulfides (LiPSs). In this context, multiscale porous structure design of noncarbonaceous materials is highly required, but has not been exploited in LSBs yet because of the absence of a facile method to control the multiscale porous inorganic materials. Here, a hierarchically porous titanium nitride (h‐TiN) is reported as a multifunctional sulfur host, integrating the advantages of multiscale porous architectures with intrinsic surface properties of TiN to achieve high‐rate and long‐life LSBs. The macropores accommodate the high amount of sulfur, facilitate the electrolyte penetration and transportation of Li+ ions, while the mesopores effectively prevent the LiPS dissolution. TiN strongly adsorbs LiPS, mitigates the shuttle effect, and promotes the redox kinetics. Therefore, h‐TiN/S shows a reversible capacity of 557 mA h g?1 even after 1000 cycles at 5 C rate with only 0.016% of capacity decay per cycle. 相似文献
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Strength of Materials - A 316L/Q345R stainless steel-clad plate after hot rolling was subjected to three heat treatments: rapid cooling, rapid cooling and tempering, high-temperature rapid cooling,... 相似文献
999.
Scientometrics - Co-citation analysis is one of the most important methods in information science. Journal co-citation analysis has been widely used to analyze the relevance, relationship and... 相似文献
1000.
In recent years, Researchers have proposed the concept of Energy Harvesting Backscatter Wireless Networks (EHBWN). EHBWN usually consists of one sink and several backscatter nodes. Backscatter nodes harvest energy from their environment and communicate with sink through backscattering the carrier wave transmitted by sink. Although a certain amount of access protocols for Energy Harvesting Wireless Networks have been present, they usually do not take the sink’s receiver sensitivity into account, which makes those protocols unsuitable in practice. In this paper, we first give an analysis of the backscatter channel link budget and the relationship between the effective communication range and uplink data rate. After that, we point out that a single uplink data rate for all the backscatter nodes is no longer suitable due to the constraint of sink receiver sensitivity. Later we propose Multi-rate Polling which divides the network into different uplink data rata regions to make sure the correct packet reception by the sink and improve the network performance. Multi-rate Polling also introduces a parameter K, through adjusting it, we can achieve the trade-off between network throughput and fairness to meet the requirement under various scenarios. We validate Multi-rate Polling under different networks and average harvesting rates through simulation. The result shows that the proposed protocol can effectively improve the network performance and has excellent scalability, which makes it suitable for EHBWN. 相似文献