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排序方式: 共有401条查询结果,搜索用时 15 毫秒
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Mengmeng Guan Lei Wang Shishun Zhao Bin Peng Wei Su Zhexi He Guohua Dong Tai Min Jing Ma Zhongqiang Hu Wei Ren Zuo‐Guang Ye Ce‐Wen Nan Ziyao Zhou Ming Liu 《Advanced functional materials》2019,29(1)
Ferromagnetic insulator thin film nanostructures are becoming the key component of the state‐of‐the‐art spintronic devices, for instance, yttrium iron garnet (YIG) with low damping, high Curie temperature, and high resistivity is explored into many spin–orbit interactions related spintronic devices. Voltage modulation of YIG, with great practical/theoretical significance, thus can be widely applied in various YIG‐based spintronics effects. Nevertheless, to manipulate ferromagnetism of YIG through electric field (E‐field), instead of current, in an energy efficient manner is essentially challenging. Here, a YIG/Cu/Pt layered nanostructure with a weak spin–orbit coupling interaction is fabricated, and then the interfacial magnetism of the Cu and YIG is modified via ionic liquid gating method significantly. A record‐high E‐field‐induced ferromagnetic resonance field shift of 1400 Oe is achieved in YIG (17 nm)/Cu (5 nm)/Pt (3 nm)/ionic liquid/Au capacitor layered nanostructures with a small voltage bias of 4.5 V. The giant magnetoelectric tunability comes from voltage‐induced extra ferromagnetic ordering in Cu layer, confirmed by the first‐principle calculation. This E‐field modulation of interfacial magnetism between light metal and magnetic isolator may open a door toward compact, high‐performance, and energy‐efficient spintronic devices. 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
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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
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大花无柱兰是一种珍稀兰科植物,具有一定的观赏和药用价值,但数量十分稀少,该物种亟待保护。本研究采用SRAP分子标记技术,对10个居群的115份DNA样品进行PCR扩增,并开展遗传多样性分析。从81对引物中筛选出9个条带清晰、多态性好、重复性高的引物组合,共扩增得到305条谱带。在物种水平上,多态性比率(PPB)为100%,Nei’s基因多样性指数(H )为0.209 8,Shannon’s指数(I )为0.340 2;在居群水平上,PPB为24.59%~52.13%,H 为0.079 6~0.165 5,I 为0.120 9~0.252 3。居群水平上,基因分化度(Gst)为0.520 9,基因流(Nm)为0.459 9,遗传距离为0.091 9~0.198 4。UPGMA聚类结果表明,10个居群可分为3大类,地理距离相近的居群优先聚集。大花无柱兰的遗传多样性较为丰富,居群间存在一定的遗传分化和基因交流,可采用就地保护和人工栽培等方式加以保护。 相似文献
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Cysteine‐Mediated Intracellular Building of Luciferin to Enhance Probe Retention and Fluorescence Turn‐On 下载免费PDF全文
Mengmeng Zheng Haixiao Huang Mi Zhou Yuqi Wang Prof. Yan Zhang Prof. Deju Ye Prof. Hong‐Yuan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(29):10506-10512
The development of sensitive and selective small molecular probes that enable real‐time detection of endogenous cysteine (Cys) has become an attractive topic because of the essential roles played by Cys in controlling the cellular nitrogen balance and in maintaining biological redox homeostasis. Herein, we report a Cys‐specific probe, 2‐cyanobenzothiazol‐6‐yl acrylate (CBTOA), that shows not only fluorescence turn‐on for sensitive detection of endogenous Cys but also enhanced probe retention inside cells for real‐time monitoring of Cys levels upon external stimulation. Cys‐mediated intracellular formation of luciferin from CBTOA was the key strategy leading to this new type of fluorogenic probe. CBTOA showed fast response to Cys in living cells and liver tissue slices with high sensitivity and selectivity. By using CBTOA as a real‐time probe, we were able to monitor the change in Cys levels in living HeLa cells under ROS‐induced oxidative stress as well as in human mesenchymal stem cells during adipogenic differentiation. 相似文献
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Jian Zhou Xi Li Linlin Yang Songlin Yan Mengmeng Wang Dan Cheng Qi Chen Yulin Dong Peng Liu Weiquan Cai Chaocan Zhang 《Analytica chimica acta》2015
A novel electrochemical sensor based on Cu-MOF-199 [Cu-MOF-199 = Cu3(BTC)2 (BTC = 1,3,5-benzenetricarboxylicacid)] and SWCNTs (single-walled carbon nanotubes) was fabricated for the simultaneous determination of hydroquinone (HQ) and catechol (CT). The modification procedure was carried out through casting SWCNTs on the bare glassy carbon electrode (GCE) and followed by the electrodeposition of Cu-MOF-199 on the SWCNTs modified electrode. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) were performed to characterize the electrochemical performance and surface characteristics of the as-prepared sensor. The composite electrode exhibited an excellent electrocatalytic activity with increased electrochemical signals towards the oxidation of HQ and CT, owing to the synergistic effect of SWCNTs and Cu-MOF-199. Under the optimized condition, the linear response range were from 0.1 to 1453 μmol L−1 (RHQ = 0.9999) for HQ and 0.1–1150 μmol L−1 (RCT = 0.9990) for CT. The detection limits for HQ and CT were as low as 0.08 and 0.1 μmol L−1, respectively. Moreover, the modified electrode presented the good reproducibility and the excellent anti-interference performance. The analytical performance of the developed sensor for the simultaneous detection of HQ and CT had been evaluated in practical samples with satisfying results. 相似文献