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941.
Flexible and lightweight supercapacitors with superior mechanical flexibility and outstanding capacity are regarded as an ideal power source for wearable electronic devices. Meanwhile, incorporating additional novel characters such as transparency and electrochromism can further benefit the development of smart supercapacitors. Nevertheless, the application of the commonly used planar-structural current collectors is seriously restricted by their intrinsic properties such as poor rigidity, large thickness, and limited loading surface area. Flexible and ultralight current collectors with 3D architecture, high conductivity, and easy integration are believed to be the most appropriate alternatives to build high-performance supercapacitors. In this study, a novel and scalable manufacturing technique is developed to produce a flexible and ultralight 3D Ni micromesh (3D NM) current collector for supercapacitor. Flexible smart supercapacitor integrated by 3D NM and high active Ni–Co bimetallic hydroxide (3D NM@NiCo BH) delivers a considerable rate performance (60.6% capacity retention from 1 to 50 mA cm−2). Furthermore, the fabricated hybrid supercapacitor device integrated with electrochromic functionality can visually indicate the energy level by a color display. This flexible electrochromic supercapacitor based on ultralight 3D Ni micromesh provides a novel insight into multifunctional energy storage systems for smart wearable electronic devices.  相似文献   
942.
The intriguing surface sensitivity of the single-crystalline semiconductor nanowires offers tremendous opportunity in tuning the physical properties of nanophotonic and nanoelectronic devices for versatile applications. Particularly, in the pursuit of emerging photoelectrochemical (PEC)-type devices, significant efforts have been devoted to understanding the charge transfer dynamics between the nanowires and the electrolyte. Here, a PEC-type ultraviolet photodetector consisting of GaN p-n junction nanowires as photoelectrodes is constructed. It is found that two competing charge transport processes at the nanowires’ surface as well as in the p-n junction co-determine the photoresponsive behavior of the device. Furthermore, the surface platinum (Pt) decoration has successfully tuned the charge transfer dynamics by enhancing the charge transport efficiency at the surface, resulting in a twenty-fold increase of the photocurrent compared to the pristine GaN nanowires. Theoretical calculations reveal that the newly formed electronic states at the Pt/GaN interface account for the improved charge transfer at the surface, and the optimal hydrogen adsorption energy contributes to the boosted PEC reaction rate. The synergy of these two effects uncover the underlying mechanism of the high photoresponse of the constructed Pt/GaN-nanowires-based PEC photodetectors.  相似文献   
943.
Most anticancer drugs with broad toxicities are systematically administrated to cancer patients and their distribution in tumors is extremely low owing to hypoxia, which compromises the therapeutic efficacies of these cancer drugs. Consequently, a preponderant proportion of cancer drugs is distributed in off-target-healthy tissues, which often causes severe adverse effects. Precision cancer therapy without overdosing patients with drugs remains one of the most challenging issues in cancer therapy. Here, a novel concept of nanopoxia is presented, which is a tumor-hypoxia-based photodynamic nanoplatform for the release of therapeutic agents to achieve precision cancer therapy. Under tumor hypoxia, exposure of tumors to laser irradiation induces the fracture of polymer outer shell and produces anticancer reactive oxygen species, and switches 2D antimonene (Sb) nanomaterials to cytotoxic trivalent antimony to synergistically kill tumors. In preclinical cancer models, delivery of Sb nanomaterials to mice virtually ablates tumor growth without producing any detectable adverse effects. Mechanistically, the tumor hypoxia-triggered generation of trivalent antimony displays direct damaging effects on cancer cells and suppression of tumor angiogenesis. Together, the study provides a proof-of-concept of hypoxia-based precision cancer therapy by developing a novel nanoplatform that offers multifarious mechanisms of cancer eradication.  相似文献   
944.
“高职信息技术”课程存在教学内容薄弱、教学功利性强、学生创新能力不足等问题。在新课标及学院“五有人才”培养目标的指导下,经过调查研究,文章提出了线上、线下相混合,在线精品课程、在线实训平台与课堂教学三结合的教学模式,以及调整课程内容与授课时长、开发符合新课标的课程资源、建设在线实训平台、培养高质量教师团队的改革举措。  相似文献   
945.
为了提高停车场的服务水平,停车场智能管理系统是必不可少的。它已经在大部分停车场发挥着重要作用,在为人们停车带来方便的同时也具有良好的社会效益和经济效益。在大、中型地下车库中,车主返回停车场时,由于停车场太大或者地形不熟,车主容易找不到车,故提出了智能反向寻车系统。该系统可以帮助车主尽快找到车辆停放的区域,提高车主的满意度,同时加快停车场的车辆周转,提高使用率和收入。目前市场上虽已有一些寻车引导系统,但都是通过监控查找车辆的区域位置,是通过终端主机进行查询的,不够方便快捷。建立一套智能化高速有效的智能反向寻车系统,使停车服务做到安全、简便、准确,并且使造价和经营成本控制在适当范围,是当前停车场管理的趋势。  相似文献   
946.
本文介绍了零信任思想及相关概念,结合企业安全战略目标预期、现状调研、规划蓝图、规划设计等内容,提出了基于运营商现网建设情况的零信任架构解决方案,根据实际情况适当加强和补充了安全短板,建立以用户身份为中心,以终端设备、访问行为为决策要素的安全架构,总结出适合运营商网络的零信任架构的场景落地及推广建议。  相似文献   
947.
针对目前生物识别技术在穿戴式设备上应用的缺陷,提出一种可应用于可穿戴设备上的生物识别方法。利用300KHz-1.5GHz的电磁波在人体通信信道传输中产生的幅度衰减特性曲线作为生物特征。为了验证此方法的可行性,首先,利用矢量网络分析仪测量生物特征;其次,提取数据的梯度,使用支持向量机进行分类器模型训练和测试。验证结果与直接对采集的生物特征进行分析的方法对比,引入梯度的分析方法使得正确识别率从90.45%提高到94.54%、等错误率从0.95%降低到0.14%、接收者操作特征曲线下面积从0.9971增加到0.9999。因此,基于人体通信的身份识别方法可为穿戴式设备的身份认证系统研究提供一种方法。  相似文献   
948.
One main task for domain experts in analysing their nD data is to detect and interpret class/cluster separations and outliers. In fact, an important question is, which features/dimensions separate classes best or allow a cluster‐based data classification. Common approaches rely on projections from nD to 2D, which comes with some challenges, such as: The space of projection contains an infinite number of items. How to find the right one? The projection approaches suffers from distortions and misleading effects. How to rely to the projected class/cluster separation? The projections involve the complete set of dimensions/features. How to identify irrelevant dimensions? Thus, to address these challenges, we introduce a visual analytics concept for the feature selection based on linear discriminative star coordinates (DSC), which generate optimal cluster separating views in a linear sense for both labeled and unlabeled data. This way the user is able to explore how each dimension contributes to clustering. To support to explore relations between clusters and data dimensions, we provide a set of cluster‐aware interactions allowing to smartly iterate through subspaces of both records and features in a guided manner. We demonstrate our features selection approach for optimal cluster/class separation analysis with a couple of experiments on real‐life benchmark high‐dimensional data sets.  相似文献   
949.
Zhang  Zhaoyang  Jiang  Yujia  Huang  Lei  Nie  Xin  Liu  Gao 《Microsystem Technologies》2017,23(6):1695-1701

The experiment of laser thermal enhanced electrochemical deposition was investigated in this paper and the deposition layer of copper was obtained when laser irradiated the stainless steel substrate through the electrolyte. Then the scanning electron microscope was utilized to observe the surface morphology and cross-sectional morphology of the deposition layer. According to morphology observed, the laser thermal effect was discussed and the mechanical of laser enhanced electrochemical deposition was analyzed. The results show that the thermal effect of laser could increase the electrode potential and speed up the reduction reaction rate of electrochemical deposition. Compared with the ordinary electrodeposition, the grain size of electrodeposition has also been greatly reduced. When the laser energy was 0.2 mJ (20 kHz), the deposition rate was better and when the laser energy was between 0.2 mJ (20 kHz) and 0.4 mJ (20 kHz), the deposition layer with high tensile strength was gained. The results are useful to the development of the later electrochemical machining technology.

  相似文献   
950.
通过等温吸附试验,研究了超高交联树脂NDA-66对邻苯二甲酸(ο-PA)的吸附性能及吸附行为,同时优化了NDA-66处理增塑剂DBP生产废水吸附-脱附工艺参数。经过初步筛选发现,NDA-66树脂对ο-PA具有良好的吸附性能,在温度为15℃、30℃和45℃条件下分别测定了吸附平衡数据,ο-PA在NDA-66树脂上的吸附平衡符合Freundlich等温吸附方程,温度对吸附的影响较大。参数优化试验结果表明:树脂吸附最佳工艺参数是:pH 2.0~2.4,温度30℃,流速为1.5 BV/h;树脂脱附最佳工艺参数,脱附剂用量及组成为1 BV 8%NaOH+2 BV H_2O,脱附温度为55℃,脱附流速为1.5 BV/h。  相似文献   
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