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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
2.
3.
陶瓷绘画最早可以追溯到彩陶时期,陶瓷与绘画相互交融发展。至今,文人画的审美精神和文化内涵一直影响着当代陶瓷绘画,在画面的表现形式和内在精神上都极具中国传统文化的艺术精神。 相似文献
4.
充气膜承冰壳结构是通过对充气
膜喷溅液体材料,待其凝结成型后撤除充气
膜形成的冰壳结构,该技术始于20世纪40年
代的充气膜承薄壳混凝土结构。文章通过比
对混凝土薄壳和冰壳的差异性,梳理充气膜
承薄壳结构的发展主线,对其形态设计方法
进行总结。结合“2017哈尔滨国际冰雪建造
节”相关建造实践,从施工方案的拟定与实
践、施工材料的选择与工艺以及施工工法的
对比与分析三方面对充气膜承冰壳结构形态
设计与建造实践进行总结与备忘,并对其后
期维护相关条件与技术进行讨论。 相似文献
5.
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
6.
Shenghong Huang 《计算机系统科学与工程》2020,35(3):215-222
Today, highly sophisticated technology has changed the lives of most individuals worldwide. In the field of graphic design, the emergence and development
of digital multimedia communication forms have had a crucial impact on the creative process of graphic design and even the process of communication,
offering more opportunities and more exciting challenges to this domain. And with the continuous improvement of people’s material culture and spiritual
culture, the digital age has enriched people’s production and life. Especially in the application of digital multimedia in graphic design, the changes caused
by the emergence of digital multimedia focus mainly on the visual expression. With the continuous application of digital multimedia communication forms,
the graphic design closely related to it has been affected to some extent. In order to meet the changing data needs of people, graphic design has also begun
to adjust accordingly. Therefore, this paper analyzes the relationship between digital multimedia and graphic design from the perspective of art design,
systematically determines the relationship between multimedia and graphic design specific design subjects, and studies the influence of digital multimedia
technology on graphic design. 相似文献
7.
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
8.
After the “imported” urban forms, which originated from foreign cultures, were transplanted into Chinese cities, they generate brand-new urbanscape but suffer from a lack of cultural roots and a disconnection with the mainstream of contemporary urban planning. Thus, their current value and potential in urban renewal are questioned. The study takes the circular–radial space from the Baroque cities as an example to clarify the motivation of its import from the west to northeast China. It further clarifies their adaptive changes in form and function in the local urban context, through a case study on Dalian City. The study finds that different geometric patterns of existing circular–radial space were influenced by European, American, and Japanese urban planning theories to varying degrees, but with equal emphasis on symbolism and functionality. Their implementation in Dalian has a continuity in time and space. But due to the changes in topography, traffic, and planning concepts, their forms and functions tend to be independent, their connection weakens, and their importance recedes after the street network. The circular–radial space in Dalian led to distinctive urbanscape. But during their inheritance and transformation, the rationality of new forms and functions, as well as the necessity of continuing the initial ones need to be dialectically considered, so as to avoid dogmatic revival and antique reproduction. Finally, the study reconsiders the concept of “localization” of “imported” urban form, and constructs a general research pattern to provide a new perspective for understanding the transformation of similar types of urban forms. 相似文献
9.
《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
10.
《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