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71.
Jia-Nan Ma Yong-Lai Zhang Dong-Dong Han Jiang-Wei Mao Zhao-Di Chen Hong-Bo Sun 《国家科学评论(英文版)》2020,7(4):775
Graphene-based actuators featuring fast and reversible deformation under various external stimuli are promising for soft robotics. However, these bimorph actuators are incapable of complex and programmable 3D deformation, which limits their practical application. Here, inspired from the collective coupling and coordination of living cells, we fabricated a moisture-responsive graphene actuator swarm that has programmable shape-changing capability by programming the SU-8 patterns underneath. To get better control over the deformation, we fabricated SU-8 micropattern arrays with specific geometries and orientations on a continuous graphene oxide film, forming a swarm of bimorph actuators. In this way, predictable and complex deformations, including bending, twisting, coiling, asymmetric bending, 3D folding, and combinations of these, have been achieved due to the collective coupling and coordination of the actuator swarm. This work proposes a new way to program the deformation of bilayer actuators, expanding the capabilities of existing bimorph actuators for applications in various smart devices. 相似文献
72.
Xier Luo Yu Zhou Bing Zhang Yi Zhang Xiaobo Wang Tong Feng Zhipeng Li Kuiqing Cui Zhiqiang Wang Chan Luo Hui Li Yanfei Deng Fenghua Lu Jianlin Han Yongwang Miao Huaming Mao Xiaoyan Yi Cheng Ai Shigang Wu Alun Li Zhichao Wu Zijun Zhuo Do Da Giang Bikash Mitra Mohammad Farhad Vahidi Shahid Mansoor Sahar Ahmed Al-Bayatti Eka Meutia Sari Neena Amatya Gorkhali Sigit Prastowo Laiba Shafique Guoyou Ye Qian Qian Baoshan Chen Deshun Shi Jue Ruan Qingyou Liu 《国家科学评论(英文版)》2020,7(3):686
Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production. 相似文献
73.
Peijie Chen Lijuan Mao George P.Nassis Peter Harmer Barbara E.Ainsworth Fuzhong Li 《运动与健康科学(英文)》2020,9(2):103-104
The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7. 相似文献
74.
Qingyang Hu Jin Liu Jiuhua Chen Bingmin Yan Yue Meng Vitali B Prakapenka Wendy L Mao Ho-Kwang Mao 《国家科学评论(英文版)》2021,8(4):16-23
Understanding the mineralogy of the Earth''s interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle (DLM, 1800–2890 km in depth) and observed surprising mineralogical transformations in the presence of water. Ferropericlase, (Mg, Fe)O, which is the most abundant oxide mineral in Earth, reacts with H2O to form a previously unknown (Mg, Fe)O2Hx (x ≤ 1) phase. The (Mg, Fe)O2Hx has a pyrite structure and it coexists with the dominant silicate phases, bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for (Mg0.6Fe0.4)O or beyond 2300 km for (Mg0.7Fe0.3)O. The (Mg, Fe)O2Hx is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences (Mg2+, Fe3+ and H+). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DLM and an internal source for modulating oxygen in the atmosphere. 相似文献
75.
高等学历信号的有效性是指高等学历信号能否对能力不同的人进行有效甄别,而高等教育体制会对高等学历信号的有效性产生重要的影响。中国目前的高等教育体制使高等学历信号失效,失效后的高等学历信号对劳动力就业市场、对社会生产率、对个人的选择及对高等教育本身都产生了极为深远的影响。 相似文献
76.
毛若寒 《自然科学博物馆研究》2023,(5):32-40
自然科技类博物馆面临着如何提高展览传播有效性的挑战。本文以语境化阐释为切入点,探讨了其理念、方法和实践在提升自然科技类博物馆传播有效性方面的作用和意义。语境化阐释是一种将展品置于其原生或新生的关联网络中,揭示展品与其相关的人、物、环境、事件等之间的联系,从而增强展品的信息量、意义和价值的阐释方法。本文分析语境化阐释的内涵、机制、目标及作用,并从历史演变和现实功能的视角,剖析“语境化阐释”助力“传播有效性”提升的内在逻辑。最后,提出基于“展品”语境网络的可视化编织、基于“知识”的跨语境对话与跨视角重构以及基于“受众”的分众化语境化阐释系统助力路径。 相似文献
77.
78.
[目的/意义]旨在准确、合理地对专利授权数进行预测.[方法/过程]运用灰色系统理论,对待选因素进行灰关联度计算,选择关联度较高因素的统计数据,形成被比较序列,再结合参考序列建立GM(1,N)模型,对专利授权数进行预测和误差检验.[结果/结论]通过与常规GM(1,N)模型对比,建立的GM(1,6)模型的预测准确度优于前者... 相似文献
79.
课程思政的目标是立德树人,将德智体美劳贯穿育人的全过程,把学生培养成德智体美劳全面发展的高素质人才是一切教育的根本.课程思政对会计专业课程改革至关重要.本文从财务会计岗位课程思政改革的特点出发,设计岗位课程的思政点,并探索切实可行的岗位课程思政实践路径. 相似文献
80.
[目的/意义]近年来,在教育部下发关于加强大中小学国家安全教育的文件以后,学术界有关国家安全学的研究呈现活跃之势,但其中对该学科理论体系构建的深入探究较为缺乏。[方法/过程]国家安全学作为一门新兴学科,“求理”的理论体系构建和“致用”服务国家安全实践方面的研究同样重要,二者应兼顾思考。从学科理论体系建设层面探讨国家安全学学科建设内在逻辑,既能为该学科的未来建设发展提供参考,也能给国家安全学提供新的理论契机。[结果/结论]具体而言包括分析该学科建构的理论基础,基于现实的基本面向和理论与实践结合层面的发展方向的深入思考,在此基础上指明了国家安全学科领域的相关研究既应立足本土,也需有全球视野,为国家治理体系和治理能力现代化承担责任。 相似文献