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991.
Changsheng Wu Peng Jiang Wei Li Hengyu Guo Jie Wang Jie Chen Mark R. Prausnitz Zhong Lin Wang 《Advanced functional materials》2020,30(3)
Transdermal drug delivery (TDD) systems with feedback control have attracted extensive research and clinical interest owing to their unique advantages of convenience, self‐administration, and safety. Here, a self‐powered wearable iontophoretic TDD system that can be driven and regulated by the energy harvested from biomechanical motions is proposed for closed‐loop motion detection and therapy. A wearable triboelectric nanogenerator (TENG) is used as the motion sensor and energy harvester that can convert biomechanical motions into electricity for iontophoresis without stored‐energy power sources, while a hydrogel‐based soft patch with side‐by‐side electrodes is designed to enable noninvasive iontophoretic TDD. Proof‐of‐concept experiments on pig skin with dyes as model drugs successfully demonstrate the feasibility of the proposed system. This work not only extends the application of TENG in the biomedical field, but may also provide a cost‐effective solution for noninvasive, electrically assisted TDD with closed‐loop sensing and treatment. 相似文献
992.
Shouzhi Wang Lili Li Weidong He Yongliang Shao Yanlu Li Yongzhong Wu Xiaopeng Hao 《Advanced functional materials》2020,30(27)
Binary metal oxides (such as NiCo2O4) are regarded as attractive electrode materials for advanced energy storage devices since they offer more electrochemical activity and higher capacity than monometal oxide. However, the volume expansion and low electronic conductivity are the main bottleneck seriously hindering their application. To overcome these barriers, a novel strategy that introduces a bimetallic oxynitride layer (NiCoON) with oxygen vacancy to the surface of NiCo2O4 nanowires as an anode for Li‐ion capacitors (LICs) is proposed. The oxygen vacancy on the surface and the modulation of multiple valence states are investigated by the electron paramagnetic resonance, X‐ray photoelectron spectroscopy characterization, and first‐principles calculation. Benefiting from the merits of substantially improved electrical conductivity and increased concentration of active sites, the optimized NiCoON electrode delivers remarkable capacity (1855 mAh g?1 at 0.2 A g?1) and rate performance. The LIC device assembled by NiCoON anodes and N‐doped carbon nanowire cathodes delivers excellent rate capability, high energy density (148.5 Wh kg?1), and outstanding power density (30 kW kg?1). This study provides a new pathway for developing bimetallic oxides with an improved performance in electrochemical energy storage, conversion fields, and beyond. 相似文献
993.
Zhe Peng Xia Cao Peiyuan Gao Haiping Jia Xiaodi Ren Swadipta Roy Zhendong Li Yun Zhu Weiping Xie Dianying Liu Qiuyan Li Deyu Wang Wu Xu Ji‐Guang Zhang 《Advanced functional materials》2020,30(24)
To enable next‐generation high‐power, high‐energy‐density lithium (Li) metal batteries (LMBs), an electrolyte possessing both high Li Coulombic efficiency (CE) at a high rate and good anodic stability on cathodes is critical. Acetonitrile (AN) is a well‐known organic solvent for high anodic stability and high ionic conductivity, yet its application in LMBs is limited due to its poor compatibility with Li metal anodes even at high salt concentration conditions. Here, a highly concentrated AN‐based electrolyte is developed with a vinylene carbonate (VC) additive to suppress Li+ depletion at high current densities. Addition of VC to the AN‐based electrolyte leads to the formation of a polycarbonate‐based solid electrolyte interphase, which minimizes Li corrosion and leads to a very high Li CE of up to 99.2% at a current density of 0.2 mA cm‐2. Using such an electrolyte, fast charging of Li||NMC333 cells is realized at a high current density of 3.6 mA cm‐2, and stable cycling of Li||NMC622 cells with a high cathode loading of 4 mAh cm‐2 is also demonstrated. 相似文献
994.
Ting Pan Yu Shen Peng Wu Zhida Gu Bing Zheng Jiansheng Wu Sheng Li Yu Fu Weina Zhang Fengwei Huo 《Advanced functional materials》2020,30(34)
Thermal treatment of metal–organic frameworks (MOFs) as a post‐treatment approach has grown in popularity and resulted in various MOF‐derived materials. However, the widely used extreme thermolytic conditions (usually above 500 °C) lead to degradation in the well‐defined MOFs intrinsic properties. This work demonstrates that MIL‐101 calcined at medium‐temperature range (200–280 °C) partially breaks the coordination bonds that can introduce more accessible active sites, exhibiting a 10‐fold increase in oxidation activity while retaining its intrinsic structure and porosity. Another fascinating feature of MIL‐101 calcined in this temperature range is their temperature‐dependent shrinkage behavior, which is also found in many other types of MOFs. Based on different shrinkage ratios of various MOFs, yolk–shell MOFs@MOFs structures can be constructed through nonsacrificial template method. Overall, the structural and morphological evolution process of MOFs treated in the medium‐temperature range can open new horizons to develop efficient MOFs catalysts and design complex structures. 相似文献
995.
996.
针对比幅测向精度较低而干涉仪测向相位易模糊这一问题,提出了一种基于多波束比幅测向的圆阵相关干涉仪解模糊改进算法,实现对小型无人机方位的快速估计。首先,根据目标无人机的图传信号特征值建立离线数据库,利用改进的多波束相关比幅法对无人机来波方向进行粗略测量,通过二次插值法对“栅栏效应”造成的估计偏差进行一定修正;然后,将修正后的角度测量值对干涉仪实测相位差进行解模糊;最后,利用无模糊的相位差通过相关运算实现来波方向的精确估计。该算法将相关运算运用在比幅测向中,有效提高了干涉仪解模糊概率。与传统的比幅测向法和干涉仪测向法相比,该算法只需3组天线就能完成测向功能,其测向精度提高至2°以内,并且该算法对天线一致性要求低,实时性高,可实际应用于圆形阵列测向体制,实现对无人机的快速测向。 相似文献
997.
998.
源代码漏洞检测是保证软件系统安全的重要手段。近年来,多种深度学习模型应用于源代码漏洞检测,极大提高了漏洞检测的效率,但还存在自定义标识符导致库外词过多、嵌入词向量的语义不够准确、神经网络模型缺乏可解释性等问题。基于此,该文提出了一种基于卷积神经网络(CNN)和全局平均池化(GAP)可解释性模型的源代码漏洞检测方法。首先在源代码预处理中对部分自定义标识符进行归一化,并采用One-hot编码进行词嵌入以缓解库外词过多的问题;然后构建CNN-GAP神经网络模型,识别出包含CWE-119缓冲区溢出类型漏洞的函数;最后通过类激活映射(CAM)可解释方法对结果进行可视化输出,标识出可能与漏洞相关的代码。通过与Russell等人提出的模型以及Li等人提出的VulDeePecker模型进行对比分析,表明CNN-GAP模型能达到相当甚至更好的性能,且具有一定的可解释性,便于研究人员对漏洞进行更深入的分析。 相似文献
999.
本文对通信机房的电磁干扰问题及相关规范做了详细的综述,并以某省通信生产楼拟建局址电磁环境的实测数据为例,对高压输变电系统对通信机房的电磁干扰影响进行分析和论证.对今后通信机房的建设及相关规范的更新与制定具有较好的参考价值. 相似文献
1000.
基于IMS的多媒体彩铃业务的设计和实现 总被引:2,自引:0,他引:2
多媒体彩铃(MRBT)业务是一种采用多种媒体作为回铃音的增值业务.结合IMS网络体系结构和MRBT业务属性,提出一种利用多媒体彩铃业务平台来实现MRBT业务的方案,包括系统设计和基于SIP(会话发起协议)的信令流程.同时,给出相关的特点分析并进行总结. 相似文献