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181.
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计量技术档案除了可以显示出技术机构运行的情况,方便工作人员及时发现并调整体系运行过程中存在的问题,使所有工作有序进行以外,还为日常检定工作的溯源和改进提供了主要凭证和强大动力。在计量事业发展的同时,档案管理也发扬着其日益重要的作用,怎样管理好计量技术档案是当前依法治检中不可或缺的一项重要工作,该篇文章将围绕计量技术单位该怎样安排有限的人力资源,做好各项档案管理工作,保证在常规工作有条不紊的进行的同时,能科学化妥善保管各种工作档案来谈谈自己的理解。 相似文献
183.
Biwei Deng Rong Xu Kejie Zhao Yongfeng Lu Sabyasachi Ganguli Gary J. Cheng 《Materials Today》2018,21(5):467-474
Manufacturing ultralight and mechanical reliable materials has been a long-time challenge. Ceramic-based mechanical metamaterials provide significant opportunities to reverse their brittle nature and unstable mechanical properties and have great potential as strong, ultralight, and ultrastiff materials. However, the failure of ceramics nanolattice and degradation of strength/modulus with decreasing density are caused by buckling of the struts and failure of the nodes within the nanolattices, especially during cyclic loading. Here, we explore a new class of 3D ceramic-based metamaterials with a high strength–density ratio, stiffness, recoverability, cyclability, and optimal scaling factor. Deformation mode of the fabricated nanolattices has been engineered through the unique material design and architecture tailoring. Bending-dominated hollow nanolattice (B-H-Lattice) structure is employed to take advantages of its flexibility, while a few nanometers of carbonized mussel-inspired bio-polymer (C-PDA) is coherently deposited on ceramics’ nanolayer to enable non-buckling struts and bendable nodes during deformation, resulting in reliable mechanical properties and outperforming the current bending-dominated lattices (B-Lattices) and carbon-based cellulose materials. Meanwhile, the structure has comparable stiffness to stretching-dominated lattices (S-Lattices) while with better cyclability and reliability. The B-H-Lattices exhibit high specific stiffness (>106?Pa·kg?1·m?3), low-density (~30?kg/m3), buckling-free recovery at 55% strain, and stable cyclic loading behavior under up to 15% strain. As one of the B-Lattices, the modulus scaling factor reaches 1.27, which is lowest among current B-Lattices. This study suggests that non-buckling behavior and reliable nodes are the key factors that contribute to the outstanding mechanical performance of nanolattice materials. A new concept of engineering the internal deformation behavior of mechanical metamaterial is provided to optimize their mechanical properties in real service conditions. 相似文献
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185.
Biodegradable Batteries: A Fully Biodegradable Battery for Self‐Powered Transient Implants (Small 28/2018) 下载免费PDF全文
186.
Meng Fanbin Wang Ying Wang Qiang Xu Xiaoling Jiang Man Zhou Xuesong He Ping Zhou Zuowan 《Nano Research》2018,11(7):3958-3958
Nano Research - The first author, Fanbin Meng, and the second author, Ying Wang, contributed equally to this work was unfortunately forgotten to write on the first pages of the main text and the... 相似文献
187.
Zan Wu Zhang Qiaochu Xu Hu Liao Fuyou Guo Zhongxun Deng Jianan Wan Jing Zhu Hao Chen Lin Sun Qingqing Ding Shijin Zhou Peng Bao Wenzhong Zhang David Wei 《Nano Research》2018,11(7):3739-3745
Nano Research - A spin-coating method was applied to obtain thinner and smoother PEO/LiClO4 polymer electrolyte films (EFs) with a lower level of crystallization than those obtained using a... 相似文献
188.
Nano Research - Copper nanowires (CuNWs) are becoming an indispensable item for next-generation transparent optical devices due to their excellent conductivity and transparency. In this work,... 相似文献
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190.
Yike Li Zhenhua Wu Congcan Shi Yizhuo Xu Aotian Chen Bin Su 《Advanced Engineering Materials》2023,25(20):2300703
Flush toilets waste a significant amount of water every day due to the unavoidable adhesions between human waste and the toilet surfaces. Super-slippery surfaces can repel complex fluids and various viscoelastic solids, however, are easily broken by mechanical abrasions. Herein, the fabrication of an abrasion-resistant super-slippery flush toilet (ARSFT) is reported using a selective laser sintering 3D printing technology. Unlike traditional super-slippery surfaces with limited thicknesses which can be easily worn away, the powder-sintered strategy endows the ARSFT not only with a self-supporting 3D complex shape but also with a porous structure that can accommodate considerable lubricants for an abrasion-resistant super-slippery property. As a result, the as-prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids. Besides liquids, the ARSFT exhibits a high resistance to sticky synthetic feces. Notably, even after being abraded to 1,000 cycles of abrasion using sandpaper, the ARSFT maintains its record-breaking super-slippery capability. The concept of the 3D-printed object with a superior abrasion-resistant slippery ability will improve the development of super-slippery materials and further save water consumption in the human society. 相似文献