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1.
《Ceramics International》2022,48(22):33115-33121
As a critical topological phase transition material, SrFeOx could play an essential role in the field of resistive memory. How to implement resistance-switching more softly and ensure the stability of materials has always been a relevant research hotspot. Regulating the oxygen environment during the deposition process of the films can effectively control the stoichiometry of the functional layer and then improve the resistance-switching characteristics of the device. In this paper, a SrFeOx hetero-film was prepared by oxygen pretreatment on the SrRuO3 surface before SrFeOx deposition, and the as-assembled micrometer-scale device exhibits a low set operating voltage of 0.6 V and favorable cycling characteristics. The SrFeOx hetero-film reveals a vertical brownmillerite superlattice-like structure with ~20 nm perovskite buffer layer, which benefits the connection and rupture of conductive filament. Additionally, XPS and UV–vis were used to analyze the bonding energy and band gap of SrFeOx hetero-film, and offers the experimental basis for the explanation of the conductive mechanism. Therefore, the device based on SrFeOx hetero-film with low operation voltage provides a reference for low power consumption research on topological phase transition material. 相似文献
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阐述了做好重整装置首次开工的几个关键因素:做好预处理开工工作,确保重整进料合格;做好重整催化剂的处理工作;把好重整进油后480℃温度关;遵守操作规程,平稳操作。 相似文献
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This study discusses the characteristics of the Periodic Autoregressive model, PAR(p), which is used to generate synthetic series of inflow energies that serve as entries for computer platforms that implement the planning and expansion of the operations of the BES – the Brazilian Electric Sector (SEB – Sistema Elétrico Brasileiro). The methodology for the design of a generating plant is presented in addition to the fundamentals of the “PAR(p) Interconfigurations” Model, which is referred to as the Inflow Energy Generation Model (IEGM) in this study. The major contribution of this study is to provide the first scientific discussion of the representation of multiple configurations using the PAR(p) model. For this purpose, several topics related to the time series are discussed, such as the definition of the model order, the matter of stationarity and the need to address possible outliers. Finally, a case study is presented, wherein the results of the estimation and generation of the described model’s scenarios are demonstrated. 相似文献
4.
《International Journal of Hydrogen Energy》2022,47(88):37192-37203
The operation types and operation window for high-purity H2 production for the sorption enhanced steam methane reforming (SE-SMR) with Ni/Al2O3 catalyst and CaO sorbent in a fixed-bed reactor are investigated by an experimentally verified 2D numerical method. Four chemical reactions including steam reforming, water gas shift, global steam reforming, and CO2 sorption are considered. The operation window is defined as the H2 and CO molar fractions at outlet satisfying both yH2,out ≥ 90% and yCO,out ≤ yCO,allow (= 1%, 2% or 3%) in dry base. Under the conditions of yH2,out and yCO,allow, there are six operation types, of which 2 types are within the operation window and 4 types are not within the operation window as the temperature, weight hourly space velocity (WHSV) and steam to methane (S/C) molar ratio vary. For a common case of S/C = 3, the operation windows for yCO,allow = 3% at WHSV = 8.5 h?1 and 42.5 h?1 are located at 570–670 °C and 640–690 °C respectively, based on the parameters in this work. The operation window of temperature is wider with decreasing WHSV, and it becomes wider remarkably as the S/C ratio increases. The lowest temperature inside the operation window is 550 °C. The effects of the temperature, WHSV and S/C ratio on the operating types, yH2,out and yCO,out are also presented and discussed in details. 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(50):21472-21491
This work focuses on investigating the adaptability of solid oxide fuel cell-gas turbine (SOFC-GT) hybrid system for ship application under uncertain factors. The effect of rapids, wind and waves on the performance of ship SOFC-GT is analyzed. In addition, a novel control system combining fuzzy logic theory, temperature feedforward and coordination factor on-line adjustment is proposed to address the problem of load disturbances caused by uncertain factors. The results show that the proposed operation strategy can shorten the thermal response time inside fuel cell stacks by almost 49.97%, meanwhile, reducing the maximum temperature changing rate at the electrochemically active tri-layer cell composed of anode, electrolyte, and cathode (PEN structure) by around 17.86%. Moreover, the reasonable matching between air flow and fuel flow is an essential prerequisite to ensure the safe and efficient operation of ship SOFC-GT. While the SOFC-GT is working at full load, the results indicate that the fuel to air ratio cannot exceed 2.56?10?2 g/g. Finally, an application scenario of the 5000-ton river-to-sea cargo ship sails from Nanjing Port to Yangshan Port (Eastern China) is conducted to analyze the operation characteristics of ship SOFC-GT under uncertain factors. Two set of 1000 kW SOFC-GT systems with the electrical efficiency of 64.66% is designed for the target ship, the results conclude that the operation strategy of each SOFC-GT system supports 50% load is beneficial in reducing the power tracking time and SOFC temperature overshoot. The average electrical efficiency of 61.45% and 61.04% are achieved in winter and summer typical days respectively in the whole voyage. 相似文献
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机电制修厂自开展设备检修业务以来,发展很快,但是由于专业检修人员少、青工多,导致职工技术素质及业务能力难以满足机修厂的快速发展,面对困难,该厂积极转变观念。探索通过设备作业指导书来保证、促进职工检修工作规范化、标准化,取得了令人满意的效果。下面根据机修厂的实践,简单介绍如何编制作业指导书,供同行参考。 相似文献
8.
中结合实例阐述了地质灾害防治工程施工监理中质量控制的关键是质量预控,工序控制是重要的质量控制方法。 相似文献
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