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1.
Given the continuing issues of environment and energy, methane dry reforming for syngas production have sparked interest among researchers, but struggled with the process immaturity owing to catalyst deactivation. This review summarizes the recent advances in the development of efficient and stable catalysts with strong resistance to coking and metal sintering, including the application of novel materials, the assessment of advanced characterizations and the compatibility to improved reaction system. One feasible option is the crystalline oxide catalysts (perovskite, pyrochlore, spinel and LDHs), which feature a fine metal dispersion and surface confinement effect via a metal exsolution strategy and exhibit superior reactivity and stability. Some new materials (h-BN, clays and MOFs) also extend the option because of their unique morphology and microstructure. It also is elaborated that progresses were achieved in advanced characterizations application, leading to success in the establishment of reaction mechanisms and attributions to the formed robust catalysts. In addition, the perspective described the upgrade of reaction system to a higher reaction efficiency and milder reaction conditions. The combination of efficient reaction systems and robust catalysts paves a way for a scaling-up application of the process.  相似文献   
2.
ABSTRACT

Contact tracing is widely considered as an effective procedure in the fight against epidemic diseases. However, one of the challenges for technology based contact tracing is the high number of false positives, questioning its trust-worthiness and efficiency amongst the wider population for mass adoption. To this end, this paper proposes a novel, yet practical smartphone-based contact tracing approach, employing WiFi and acoustic sound for relative distance estimate, in addition to the air pressure and the magnetic field for ambient environment matching. We present a model combining six smartphone sensors, prioritising some of them when certain conditions are met. We empirically verified our approach in various realistic environments to demonstrate an achievement of up to 95% fewer false positives, and 62% more accurate than Bluetooth-only system. To the best of our knowledge, this paper was one of the first work to propose a combination of smartphone sensors for contact tracing.  相似文献   
3.
Microwave lignite drying with assistance of biomass-derived char was addressed and effect of bio-char on drying rate and energy consumption was investigated in this work. Effective diffusion coefficient and activation energy for the drying process were also analyzed. The results indicated the drying process was largely dependent on the variation of sample temperature. Bio-char originated from pine wood was most favorable for lignite drying, considering its better promoting effect and advanced security. There existed an optimal bio-char addition ratio for drying process at different power. The corresponding optimal ratio was 10% at 231?W and 15% at 385?W, at which the biggest drying rate and the least energy consumption were reached. It was compared lignite drying initiated at 385?W was better for energy conservation. Effective diffusivity was improved and activation energy was simultaneously reduced, with the addition of bio-char. The minimum activation energy was 15.54?W?·?g?1, which was gained at bio-char addition ratio of 10%. The results revealed the effect of bio-char on depressing activation energy could rival that of metal-based additives. The drying process with assistance of microwave and bio-char could present technical and economical benefits on lignite upgrading.  相似文献   
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数值试井在白6-2井测试资料分析评价中的应用   总被引:1,自引:0,他引:1  
数值试井是在近来发展的一项新的试井解释技术,具有处理非均质,复杂边界油气藏问题的优点,弥补了常规解析试井技术的不足。运用数值试井解释技术,结合动、静态资料,通过对白6-1断块白6-2井测试资料的综合分析评价,确定了储层渗流参数,落实了该气藏的边界情况,为该断块下一步开发提供可靠依据。  相似文献   
6.
介绍了天然气合成油技术,天然气石油特征及代表性工艺过程,叙述了天然气合成油发展前景。  相似文献   
7.
两种超声清洗槽的声场分布比较   总被引:3,自引:0,他引:3       下载免费PDF全文
本文作者设计了一种斜底式超声清洗槽,并通过实验研究了它的声场分布,与平底式超声清洗槽相比,这种新型清洗槽深度方向的声场均匀性得么了改善,但水平方向的声场均匀性变化不大。  相似文献   
8.
油田污水中咪唑啉缓蚀剂浓度检测技术研究   总被引:5,自引:0,他引:5  
研究评价了油田污水中咪唑啉缓蚀剂浓度检测的七种方法 ,其中紫外光分析法和显色反应法适合于低浓度咪唑啉缓蚀剂检测 ,且方法简便、速度快、成本低 ,检测浓度范围 2~ 5 0mg/L。  相似文献   
9.
新型海洋涂料技术   总被引:7,自引:0,他引:7  
本文综述了符合时代要求的海洋涂料新技术及其发展趋势。  相似文献   
10.
液压集成块校核软件的编制和应用   总被引:1,自引:0,他引:1  
本文叙述了液压集成块校核软件的编制思想和方法,并重点介绍了编制过程中所使用的相关技术,同时给出部分源程序。  相似文献   
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