共查询到20条相似文献，搜索用时 15 毫秒
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Julian Opel Julian Brunner Ramon Zimmermanns Tristan Steegmans Elena Sturm Matthias Kellermeier Helmut Clfen Juan‐Manuel García‐Ruiz 《Advanced functional materials》2019,29(37)
Silica biomorphs are extraordinary inorganic superstructures formed via autocatalytic co‐precipitation and bottom‐up self‐assembly of alkaline‐earth carbonates and silica. However, they show no inherent functionality except for their striking textural motifs and curved morphologies. This work presents strategies to magnetize silica biomorphs, thus creating thermally stable ceramic microswimmers with unique elaborate shapes. This is achieved by growing super paramagnetic magnetite mesocrystals on and around the complex curved surfaces of biomorphs, while keeping their morphology and maintaining mesocrystal integrity. Selective mesocrystal formation on certain parts of the substrates is induced by chemical modification of the biomorph surface, increasing the loading of magnetite on the silica–carbonate structures and, in suitable cases, rendering them able to respond to external magnetic fields and move as microswimmer entities. In this way, the complex ultrastructure of silica biomorphs is successfully used as a template for functional ceramics. Furthermore, selective dissolution of the carbonate core from the biomorphs leads to hollow magnetic structures that could be filled with actives, thus serving as microcarriers with considerable loading capacity. 相似文献
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Jingjing Wang Lin Zhou Shengjie Xia Zisheng Luo Bin Su Xingyu Lin 《Advanced functional materials》2024,34(3):2307903
Plasmonic nanostructures that generate hot carriers and induce catalytic chemical transformations are ideal candidates for solar energy utilization. However, the existing nanostructures require multistep synthesis procedures and generate fewer hot carriers due to their narrow resonance region and limited hotspots, restricting their usage in plasmonic catalysis. Inspired by the light-harvesting behavior of the trees, the current work reports a one-step fabrication strategy via electrodeposition for direct anisotropic growth of the 3D gold nanotrees with tunable size, branches, and height. The as-synthesized nanostructures with broadband light absorption and plentiful hotspots can significantly foster hot carrier generation. The improved hot electron generation of 3D gold nanotrees is confirmed by in situ surface-enhanced Raman spectroscopy for the dimerization reaction of 4-nitrothiophenol. The energetic hot holes generated by the 3D gold nanotrees facilitate water oxidation and exhibit 18.6 times higher catalytic efficiency than Au film under 625 nm. Meanwhile, the photoelectrochemical catalysis of 3D gold nanotrees shows better performance compared with conventional Au nanospheres. This work opens up a promising avenue for fundamental studies of plasmonic catalysis via a wide variety of 3D gold nanotrees. 相似文献
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CdSe纳米晶的制备及性能表征 总被引：16，自引：2，他引：14
以巯基乙酸（RSH）为稳定剂,在水溶液中合成了稳定的CdSe纳米颗粒,通过选择沉淀得到尺寸为1.8-4.0nm的样品。通过紫外－可见吸收光谱、X－射线粉末衍射（XRD）、透射电镜（TEM）和高分辨透射电镜（HRTEM）对样品的结构及量子限制效应影响下的光学特性进行了表征;将长链的表面活性剂接枝在纳米颗粒表面,从而使只能在水溶液中分散的纳米颗粒在有机溶剂中也能很好地分散,并得到了单个颗粒的高分辨电镜图像。 相似文献
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用矢量码书和动态内插限制方法解决语音生成逆向解的非唯一性问题 总被引：1，自引：0，他引：1
本文研究运用矢量码书和动态内插限制的方法解决语音生成逆向解的非唯一性问题.表征声道的对数截面积函数的限带傅立叶余弦展开包括了偶次项,采用可变声道长度;频域声学目标增加了前N个零点频率;结合腔包形声学——几何形态映射矢量码书,为声学目标匹配得到过渡音的起始和结尾端点的零点与声道长度,并用内插方法来限定过渡点的零点频率和声道长度,从而解决非唯一性问题.计算机仿真实验表明了本方法的有效性. 相似文献
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Kun Zhou Bingyu Qi Zhongwei Liu Xinjiang Wang Yuanhui Sun Lijun Zhang 《Advanced functional materials》2024,34(52):2411671
Research on organic–inorganic hybrid materials (OIHMs) has experienced explosive growth in the past decades. The diversity of organic components allows for the introduction of various spatial scales, functional groups, and polarities, while inorganic components provide higher hardness, heat resistance, and stability, their flexible combination facilitates the formation of diverse structures. Furthermore, simple and cost-effective synthesis methods, such as room temperature solution processes and mechanochemical techniques, enable precise control over the materials' properties at different scales, thus achieving adjustable structure–performance relationships. This review will discuss the recent research progress of OIHMs within the field of optoelectronics and related optoelectronic device applications. According to the dimension of inorganic components and the nature of organic–inorganic interface, this review divides OIHMs into four structural categories. The ongoing research has revealed diverse applications for OIHMs in the fields of solar cells, light-emitting devices, detectors, and memristors. As an outlook, the potential of perovskite and 0D metal halide materials, which are currently the most studied, for enhancing optoelectronic performance and stability is discussed. 相似文献
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空穴注入层(HIL)在量子点发光二极管(QLEDs)中有重要作用。使用低温溶液法制作了MoOx纳米颗粒,将其在氧化铟锡(ITO)玻璃上旋涂成膜后使用不同温度进行退火处理,并作为空穴注入层进行量子点发光二极管的制作。实验结果表明,氧化钼薄膜有着与ITO玻璃阳极和Poly-TPD空穴传输层匹配的能级,可用作量子点发光二极管的空穴注入层,而使用经100 ℃退火处理后的MoOx薄膜作为空穴注入层的器件性能最佳：器件启亮电压为2.5 V,最高外量子效率为11.6%,在偏压为10 V时,器件的最高亮度达到27 100 cd/m2。 相似文献
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Felix R. P. Limberg Tanja Schneider Stefan Höfle Felix Reisbeck Silvia Janietz Alexander Colsmann Hartmut Krüger 《Advanced functional materials》2016,26(46):8505-8513
A new crosslinking concept based on a thermally activated one‐component building block with thermally initiated crosslinkable ynol ether is introduced. For polystyrene matrices with glass transition temperatures below the reaction temperature, full conversion is reached within 30 min at 160 °C without employing any catalysts or co‐reactants. The ynol ethers are chemically inert toward a variety of reaction conditions (e.g., radicals and strong bases) and consequently applicable to a wide range of materials for organic electronics. The crosslinkable solid compounds are bench‐stable over more than a year. The broad applicability is demonstrated with a liquid model compound and a specifically designed crosslinking monomer introduced successfully as building block into polystyrenes with pending hole transporting groups. A detailed study of crosslinking kinetics by infrared measurements as well as an alternative method of crosslinker content determination utilizing differential scanning calorimetry is presented. The crosslinkable polymer and the corresponding noncrosslinkable molecule tris(4‐(3,6‐dibutoxy‐9H‐carbazol‐9‐yl)phenyl)amine (BuO6TCTA) are synthesized and investigated as hole transport layers (HTLs) in phosphorescent organic light emitting diodes (OLEDs). OLEDs with crosslinked and noncrosslinked HTLs show efficiencies around 80 cd A?1, indicating negligible influence of the crosslinking process on the device performance while yielding better HTL durability against solvent rinsing. 相似文献
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Wei Luo Yanbin Wang Emily Hitz Yi Lin Bao Yang Liangbing Hu 《Advanced functional materials》2017,27(31)
In the last decade, few‐layer boron nitride nanosheets and monolayer BN nanosheet (BNNS) have gained much attention due to their unique physical and chemical properties. To date, BNNS can be produced by micromechanical cleavage of BN crystal, unzipping BN nanotubes, chemical vapor deposition (CVD), and solution processed exfoliation from bulk BN powder. Due to the low cost and abundance of bulk BN powder and its simple processing for potentially scalable production, great efforts have been devoted toward solution processed exfoliation. In this feature article, recent significant advances in solution processed synthesis of BNNS are summarized. In particular, the solvent choice for one‐step BN exfoliation is highlighted. Multi‐dimensional assemblies consisting of BNNS are discussed, such as BN fiber, BN paper, and BN aerogel. The emerging applications of BNNS in different fields are then focused on, especially in barrier materials, dielectrics, catalysts, and thermal management. 相似文献
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Qihan Liu Chun Zhao Ivona Z. Mitrovic Wangying Xu Li Yang Ce Zhou Zhao 《Advanced Electronic Materials》2020,6(8)
Solution‐processed metal‐oxide thin films have been widely studied in low‐power and flexible electronics. However, the high temperature required to form a condensed and uniform film limits their applications in flexible and low‐cost electronics. Here, a novel and environmental‐friendly comproportionation reaction synthesis (CRS) is presented to obtain amorphous aluminum oxide (AlOx) thin films for solution‐processed thin‐film transistors (TFTs) employing water as the precursor solvent. The thermal decomposition of CRS‐AlOx precursor is completed at ≈300 °C, which is 100 °C lower than that of the conventional water‐induced AlOx. The morphological, optical, compositional, and electrical properties of CRS‐AlOx dielectric films are studied systematically. Meanwhile, TFTs based on water‐induced In2O3 metal oxide semiconductor layers deposited on these dielectrics at low temperatures are formed and characterized. Compared with TFTs based on conventional AlOx showing low mobility and low clockwise hysteresis, In2O3 TFTs based on CRS‐AlOx exhibit improved electrical performance and counterclockwise hysteresis in the transfer curves. Water‐induced TFTs fabricated on CRS‐AlOx formed at a low temperature of 250 °C have average mobility of 98 cm2 V−1 s−1. Through chemical composition characterization and electrical characterization, the high mobilities of TFTs based on CRS‐AlOx dielectrics are correlated to trap states, which resulted in counterclockwise hysteresis in the transfer curves. 相似文献
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在分析中国联通HSPA＋业务承载需求及技术选择的基础上,从PTN综合承载方案承载HSPA＋业务、融合多业务的统一承载平台、网络规划配置方案等方面介绍了中国联通的HSPA＋业务。 相似文献
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5G NSA网络提供了极大的带宽支持,EN-DC技术可以使运营商在5G核心网建设初期,及早地推出5G服务,以缓解某些高带宽需求的应用场景给网络带来的压力.基于多场景业务测试和信令分析,对5G高清视频回传的传统方案和创新方案进行了比较,通过网元配置,实现了5G业务演示,对创新方案进行了验证. 相似文献
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镜像综合孔径可利用较少的天线获得地球遥感所需的高空间分辨率,但是镜像综合孔径辐射测量灵敏度尚未得到深入分析。针对该问题,推导了二维镜像综合孔径辐射测量噪声特性,在此基础上,对一维/二维镜像综合孔径测量灵敏度进行了分析,开展了仿真实验,并与常规综合孔径测量灵敏度进行了分析比较。 相似文献
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Robert Schreiber Shail Aditya Scott Mahlke Vinod Kathail B. Ramakrishna Rau Darren Cronquist Mukund Sivaraman 《The Journal of VLSI Signal Processing》2002,31(2):127-142
The PICO-NPA system automatically synthesizes nonprogrammable accelerators (NPAs) to be used as co-processors for functions expressed as loop nests in C. The NPAs it generates consist of a synchronous array of one or more customized processor datapaths, their controller, local memory, and interfaces. The user, or a design space exploration tool that is a part of the full PICO system, identifies within the application a loop nest to be implemented as an NPA, and indicates the performance required of the NPA by specifying the number of processors and the number of machine cycles that each processor uses per iteration of the inner loop. PICO-NPA emits synthesizable HDL that defines the accelerator at the register transfer level (RTL). The system also modifies the user's application software to make use of the generated accelerator.The main objective of PICO-NPA is to reduce design cost and time, without significantly reducing design quality. Design of an NPA and its support software typically requires one or two weeks using PICO-NPA, which is a many-fold improvement over the industry norm. In addition, PICO-NPA can readily generate a wide-range of implementations with scalable performance from a single specification. In experimental comparison of NPAs of equivalent throughput, PICO-NPA designs are slightly more costly than hand-designed accelerators.Logic synthesis and place-and-route have been performed successfully on PICO-NPA designs, which have achieved high clock rates. 相似文献
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谭武征 《信息安全与通信保密》2012,(11):147-149
文章首先对云计算国内外发展概况做了介绍,对建立云安全存储解决方案从身份认证、加密传输、加密存储、日志审计、数据分享等方面提出了一些想法并进行了需求分析。文章提出的云存储安全服务器对安全策略模块、访问控制模块、身份管理模块、传输安全模块、监控审计模块、负载均衡模块与集中管理模块进行了系统结构分析及系统部署分析,最后对其特点进行了详细分析。分析的内容对云安全存储应用的发展起到了深刻的指导作用。 相似文献
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理想单摆模型的周期与摆角无关,本文首先给出任意摆角条件下周期公式的精确解,同时用不同方法得出周期公式的近似解。通过T0-Tπ2lg与不同周期公式的比较,结果表明在误差允许的范围内,仍可用T0来代替T计算周期。 相似文献
