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71.
Guangyong Li Ning Xi Mengmeng Yu Wai-Keung Fung 《Mechatronics, IEEE/ASME Transactions on》2004,9(2):358-365
Using atomic force microscopy (AFM) as a nanomanipulation tool has been discussed for more than a decade. However, its lack of real-time visual feedback during manipulation has hindered its wide application. Fortunately, this problem has been overcome by our recently developed augmented reality system. By locally updating the AFM image based on real-time force information during manipulation, not only can this new system provide real-time force feedback but also real-time visual feedback. The real-time visual display combined with the real-time force feedback provides an augmented reality environment, in which the operator not only can feel the interaction forces but also observe the real-time changes of the nano-environment. This augmented reality system capable of nanolithography and manipulation of nano-particles helps the operator to perform several operations without the need of a new image scan, which makes AFM-based nano-assembly feasible and applicable. 相似文献
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模式匹配在网络安全领域有着重要的应用,随着网络环境的日益复杂,模式集合也随之增加.如何高效处理千万模式集下的字符串匹配成为网络安全的瓶颈之一.本文针对多模式匹配算法AC算法和WM算法进行了研究,采用了新型基于层次扫描和子节点数目搜索的双数组AC算法;从hash函数的选取和模式串的Tree树存储对WM算法进行了优化.能有效减少系统的内存占用,提高匹配效率. 相似文献
75.
Mengmeng Liu Xiaohang Zhu Yujie Song Guanlin Huang Jiamin Wei Xiaokai Song Qi Xiao Tao Zhao Wan Jiang Xiaopeng Li Wei Luo 《Advanced functional materials》2023,33(11):2213395
Oxygen reduction reaction (ORR) and sulfur reduction reaction (SRR) play key roles in advanced batteries. However, they both suffer from sluggish reaction kinetics. Here, an interesting nitrogen doped porous carbon material that can simultaneously activate oxygen and sulfur is reported. The carbon precursor is a nitrogen containing covalent organic framework (COF), constituting periodically stacked 2D sheets. The COF structure is well preserved upon pyrolysis, resulting in the formation of edge-rich porous carbon with structure resembling stacked holey graphene. The nitrogen containing groups in the COF are decomposed into graphitic and pyridinic nitrogen during pyrolysis. These edge sites and uniform nitrogen doping endow the carbon product with high intrinsic catalytic activities toward ORR and SRR. The COF derived carbon delivers outstanding performances when assembling as cathodes in the Li-S and Li-O2 batteries. Simultaneous activation of oxygen and sulfur also enables a new battery chemistry. A proof-of-concept Li-S/O2 hybrid battery is assembled, delivering a large specific capacity of 2,013 mAh g−1. This study may inspire novel battery designs based on oxygen and sulfur chemistry. 相似文献
76.
Spatially Separated CdS Shells Exposed with Reduction Surfaces for Enhancing Photocatalytic Hydrogen Evolution 下载免费PDF全文
Mingyang Xing Bocheng Qiu Mengmeng Du Qiaohong Zhu Lingzhi Wang Jinlong Zhang 《Advanced functional materials》2017,27(35)
To the photocatalytic H2 evolution, the exposure of a reduction surface over a catalyst plays an important role for the reduction of hydrogen protons. Here, this study demonstrates the design of a noble‐metal‐free spatially separated photocatalytic system exposed with reduction surfaces (MnOx @CdS/CoP) for highly solar‐light‐driven H2 evolution activity. CoP and MnOx nanoparticles are employed as the electron and hole collectors, which are selectively anchored on the outer and inner surface of CdS shells, respectively. Under solar light irradiation, the photogenerated holes and electrons can directionally move to the MnOx and CoP, respectively, leading to the exposure of a reduction surface. As a result, the H2 evolution increases from 32.0 to 238.4 µmol h?1, which is even higher than the activity of platinum‐loaded photocatalyst (MnOx @CdS/Pt). Compared to the pure CdS with serious photocorrosion, the MnOx @CdS/CoP maintains a changeless activity for the H2 evolution and rhodamine B degradation, even after four cycles. The research provides a new strategy for the preparation of spatially separated photocatalysts with a selective reduction surface. 相似文献
77.
He Mengmeng Zheng Zhi Wang Wen-Qin Kang Zhenmei 《Multidimensional Systems and Signal Processing》2022,33(2):263-273
Multidimensional Systems and Signal Processing - In this paper, we propose a new amplitude-only method for pattern synthesis of uniform linear array (ULA) based on genetic algorithm (GA) and... 相似文献
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Full Color Emission in ZnGa2O4: Simultaneous Control of the Spherical Morphology,Luminescent, and Electric Properties via Hydrothermal Approach 下载免费PDF全文
Yang Zhang Zhijian Wu Dongling Geng Xiaojiao Kang Mengmeng Shang Xuejiao Li Hongzhou Lian Ziyong Cheng Jun Lin 《Advanced functional materials》2014,24(42):6581-6593
ZnGa2O4 and ZnGa2O4: Mn2+/Eu3+ with uniform nanosphere (diameter about 400 nm) morphology have been synthesized via a facile hydrothermal approach. XRD, Raman spectra, XPS, FT‐IR, SEM, TEM, photoluminescence (PL), and cathodoluminescecne (CL) spectra are used to characterize the resulting samples. The controlled experiments indicate the dosage of trisodium citrate and pH values are responsible for shape determination of the ZnGa2O4 products. The possible fast crystallization–dissolution–recrystallization formation mechanism for these nanospheres is presented. Under UV light and low‐voltage electron beam excitation, ZnGa2O4, ZnGa2O4: Mn2+ and ZnGa2O4: Eu3+ emit bright blue, green, and red luminescence, respectively. Based on density functional theory calculations from first principles, the green and red emission are caused by the Mn 3d and Eu 4f electronic structures, respectively. Besides, the dependence of the CL intensity on the calcination temperature and electrical conductivity of the samples is presented. The ZnGa2O4: Mn2+ nanospheres have a higher CL intensity than that of bulk samples under the same excitation condition. The realization of three primary colors from a single host material suggests that full color display based on ZnGa2O4 nanospheres might be achievable, showing that these materials have potential applications in lighting and display fields. 相似文献
80.
研究了掺铥光纤激光器的不同谐振腔结构方式。使用LD泵浦,分别采用双色镜和端面反射、高反光纤光栅和端面反射以及双色镜和低反光纤光栅构成激光器谐振腔,均获得了超过Stokes极限的斜效率。其中双色镜和端面反射腔结构下获得了最高斜效率56.9%,对应的量子效率为142%。三种腔结构下,激光光谱线宽由激光器系统所采用的反射腔的光谱特性所决定。在双色镜和端面反射腔结构下,激光器在双色镜的高反带宽内随机起振,光谱较宽;在使用光纤布拉格光栅作为激光器谐振腔的高反射腔镜和低反射腔镜的情况下,激光器都获得了2 m处的窄线宽输出,线宽受限于所使用的光纤光栅的反射带宽。 相似文献