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41.
介绍了一种键控式的采用单片机对高频函数发生电路进行程序控制的高频信号发生器的设计方案。此方案能产生方波、正弦波和三角波等信号;采用数字频率合成器,使输出信号频稳度和晶体振荡器的相当;并用键盘设置波形和频率,由LED显示。输出信号的频率分成1 MHz~16 MHz和8 kHz~999 kHz两挡。 相似文献
42.
基于云计算及图像内容分析的医学图像融合方法 总被引:3,自引:0,他引:3
提出了一种使用云计算实现基于图像内容分析的医学图像融合方法.为了设计云计算推理规则,对两幅输入图像--CT和MRI图像进行灰度直方图分析.并基于CT与MRI图像的灰度直方图与融合目的设计推理规则.将CT与MRI图像作为推理系统的两个输入,进而得到融合图像.实验结果表明,使用云推理方法得到的融合图像较之模糊推理得到的融合... 相似文献
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Wenjuan Liu Xiao Chen Xiaolong Lu Joseph Wang Yanan Zhang Zhongwei Gu 《Advanced functional materials》2020,30(39)
Controllable actuation and coordinating motion of artificial self‐propelled micro/nanomotors to mimic the motile natural microorganism systems are of great significance for constructing intelligent nanoscale machines. In particular, inorganic oxide particles have shown considerable promise in implementation of synthetic micro/nanomotors, due to their unique features and active response to environmental stimuli. This work critically reviews the recent progress in inorganic oxide‐based micro/nanomotors and focuses on their propulsion response to chemical and physical stimuli, especially emphasizing and discussing operating principles in the single engine, adaptive navigation under composite‐driven powers, and intriguing collective behaviors. The impact of oxide structure, multiple fields in motion controllability, and interaction between grouped micro/nanomotors are explored. Practical applications of individual and assembled micro/nanomotors in environmental and biomedical fields are demonstrated, including the removal of pollutants, drug delivery, cancer therapy, and in vivo imaging. Finally, current challenges for the development of novel micro/nanomotors and possible constraints toward the defined structure and accumulated toxicity are discussed along with future opportunities and directions. Owing to their facile synthesis, impressive physicochemical performances, high biocompatibility, and versatile actuations, it is expected that the association of inorganic oxides with micro/nanomotors will bring new and unique capabilities to the field of active matter. 相似文献
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高纯度多晶硅是“十二五”的发展重点,本文系统分析了我国物理法多晶硅行业发展面临的战略环境,将SWOT分析与层次分析法相结合,对关键战略环境要素进行量化分析,并构建了SWOT战略选择图,得出目前其发展的优势大于劣势,机会多于威胁。 相似文献
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Hong Tao Jie Yin Wenjuan Wu Lin Zhao Jian Ma Bo Wu 《Journal of the American Ceramic Society》2022,105(7):5003-5010
The influence of anion on structure and performance is unclear in potassium sodium niobate ((K,Na)NbO3; KNN)-based ceramics, while cation doping has been widely researched. Here, the phase structure and electrical properties are explored in MnF2-doped KNN ceramics. Significantly, sharp rhombohedral–orthorhombic (R–O) and orthorhombic–tetragonal (O–T) phase boundary as well as reduced diffusion degree is exhibited in the ceramics along with little changed phase transition temperatures due to the optimized F− content at O site, which is different from that of cation replacement for A and B sites. Notably, the domain wall motion is facilitated due to the increased A vacancy and decreased O vacancy along with strengthened polarity, originating from the higher valence state and electronegativity of F− with respect to O2−. And then, enhanced ferroelectricity is realized via MnF2 modification, the piezoelectricity is elevated in turn. This work presents a new idea of anion doping for controlling structure and properties in perovskite materials. 相似文献
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Jiang Lu Jia Zhiqian Xu Xin Chen Yili Peng Wenjuan Zhang Jiamin Wang Huimin Li Suoding Wen Jianping 《Journal of Porous Materials》2022,29(4):1071-1081
Journal of Porous Materials - Activated carbon fiber (ACF) is often used as efficient adsorption material for removal of contaminants from water. However, the propagation of microorganism on ACF... 相似文献
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