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91.
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Liuqing Yang Ce Zhang Xiwen Yu Yingfang Yao Zhaosheng Li Congping Wu Wei Yao Zhigang Zou 《国家科学评论(英文版)》2021,8(8)
Aerospace milestones in human history, including returning to the moon and manned Martian missions, have been implemented in recent years. Space exploration has become one of the global common goals, and to ensure the survival and development of human beings in the extraterrestrial extreme environment has been becoming the basic ability and technology of manned space exploration. For the purpose of fulfilling the goal of extraterrestrial survival, researchers in Nanjing University and the China Academy of Space Technology proposed extraterrestrial artificial photosynthesis (EAP) technology. By simulating the natural photosynthesis of green plants on the Earth, EAP converts CO2/H2O into fuel and O2 in an in-situ, accelerated and controllable manner by using waste CO2 in the confined space of spacecraft, or abundant CO2 resources in extraterrestrial celestial environments, e.g. Mars. Thus, the material loading of manned spacecraft can be greatly reduced to support affordable and sustainable deep space exploration. In this paper, EAP technology is compared with existing methods of converting CO2/H2O into fuel and O2 in the aerospace field, especially the Sabatier method and Bosch reduction method. The research progress of possible EAP materials for in-situ utilization of extraterrestrial resources are also discussed in depth. Finally, this review lists the challenges that the EAP process may encounter, which need to be focused on for future implementation and application. We expect to deepen the understanding of artificial photosynthetic materials and technologies, and aim to strongly support the development of manned spaceflight. 相似文献
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文献管理工具是一种可以有效提高科研工作者学习研究效率的软件,移动终端上的文献管理工具将用户从PC中解脱出来,让用户可以随时随地阅读、管理参考文献.论文选取五款典型的移动终端上的文献管理工具,采用ISO/IEC9126-2000模型,分别从功能性、效率性、易用性、可移植性四个方面进行比较.最后,针对比较结果,指出目前移动终端的文献参考工具具有网络搜索功能薄弱、共享方式少、检索方式单一和书目信息导出方面的功能缺失等不足. 相似文献
95.
本文在基于对体育院校实验班群体特征以及影响该群体英语水平提高因素分析的基础上,主要从教学理念、教学模式、课程设置与教材选择、教学内容与教学手段、评估体系等五个方面阐述体育院校实验班英语教学的创新。 相似文献
96.
In this work, the problem of non-fragile sliding mode control is investigated for a class of uncertain switched systems with state unavailable. First, a non-fragile sliding mode observer is constructed to estimate the unmeasured state. And then, a state-estimate-based sliding mode controller is designed, in which a weighted sum approach of the input matrices is utilized to obtain a common sliding surface. It is shown that the reachability of the specified sliding surface can be ensured by the present sliding mode controller. Moreover, the exponential stability of the sliding mode dynamics is analyzed by adopting the average dwell time method. Finally, a numerical simulation is given to demonstrate the effectiveness of the results. 相似文献
97.
We present in this paper a method for obtaining a low cost and high replication precision 2D (two dimensional) nanofluidic chip with a PET (polyethylene terephthalate) sheet, which uses hot embossing and a thermal bonding technique. The hot embossing process parameters were optimized by both experiments and the finite element method to improve the replication precision of the 2D nanochannels. With the optimized process parameters, 174.67 ± 4.51 nm wide and 179.00 ± 4.00 nm deep nanochannels were successfully replicated into the PET sheet with high replication precision of 98.4%. O2 plasma treatment was carried out before the bonding process to decrease the dimension loss and improve the bonding strength of the 2D nanofluidic chip. The bonding parameters were optimized by bonding rate of the nanofluidic chip. The experiment results show that the bonding strength of the 2D PET nanofluidic chip is 0.664 MPa, and the total dimension loss of 2D nanochannels is 4.34 ± 7.03 nm and 18.33 ± 9.52 nm, in width and depth, respectively. The fluorescence images demonstrate that there is no blocking or leakage over the entire micro- and nanochannels. With this fabrication technology, low cost polymer nanochannels can be fabricated, which allows for commercial manufacturing of nano-components. 相似文献
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在高中学习阶段,高中语文作为一门重要的基础性语言课程,对于培养高中生的文学素养与语言能力发挥着至关重要的作用。本文首先对普通高中语文教学中存在的诸多矛盾与问题进行了深入的分析,然后有针对性地提出了一系列行之有效的解决普通高中语文教学矛盾与问题的对策与措施,以期能够有效提高普通高中语文的教学质量和教学成效。 相似文献
100.