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991.
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.
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.
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.
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.
对硅基二氧化硅阵列波导光栅解复用器(AWG DEMUX)的偏振相关损耗(PDL)进行了优化。理论分析了引起AWG偏振相关性的物理因素以及消除偏振相关性的工艺方法和条件。利用化学气相沉积、光刻和刻蚀等半导体工艺制备了AWG DEMUX芯片,并结合理论分析对包层材料中的硼(B)、磷(P)含量进行了优化调整,成功地将芯片的PDL降低至0.12 dB,使PDL参数满足芯片的商用化需求。  相似文献   
997.
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   
998.
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   
999.
宽带网络市场营销策略探讨   总被引:1,自引:0,他引:1  
本文简单介绍了宽带网络市场营销的总体策略,根据客户不同的业务需求进行了客户市场细分.并对市场营销的一些方法和服务方式做了详细分析和综述.  相似文献   
1000.
本文讨论了东信北邮信息技术有限公司位置服务平台的系统总体结构设计、功能模块设计、进程拓扑图.  相似文献   
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