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971.
本文对比介绍了JJF1396-2013《频谱分析仪校准规范》与GJB/J 5859-2006《宽频带频谱分析仪检定规程》的检定校准项目、方法及相关要求,为频谱分析仪的检定校准工作开展提供参考借鉴。 相似文献
972.
973.
974.
Mechanical Properties and Interlaminar Fracture Toughness of Glass‐Fiber‐Reinforced Epoxy Composites Embedded with Shape Memory Alloy Wires
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Li‐Dan Xu Ming‐Fang Shi Xiao‐Yu Sun Zhen‐Qing Wang Bin Yang 《Advanced Engineering Materials》2018,20(3)
975.
Engineering High‐Performance MoO2‐Based Nanomaterials with Supercapacity and Superhydrophobicity by Tuning the Raw Materials Source
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Yunqiang Zhang Song Yang Shulan Wang Hua Kun Liu Li Li Shi Xue Dou Xuan Liu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(25)
Herein, a simple self‐assembly method is proposed for the fabrication of MoO2‐based superhydrophobic material with record high contact angles (contact angle up to about 173°) for conductive metal oxides on hard/soft substrates. The spin‐coated surface demonstrates excellent oil–water separation efficiency (>98%) after 50 cycles and robust corrosion resistance after immersion into different pH solutions for 20 d. These water‐resistant coatings retain excellent superhydrophobicity after oil immersion, knife‐scratch, and long‐cycle sandpaper abrasion, which is not observed on most artificial surfaces. Meanwhile, the functionality switching from superhydrophobicity to supercapacity, which have an inverse relationship in aqueous solutions because of poor electrode wettability, is achieved simply by editing the raw materials source. Tuning of the raw materials leads to the same product MoO2/graphitic carbon with different morphologies and functionalities. Different from superhydrophobic MoO2/carbon ball flowers, MoO2 nanotubes with carbon exhibit excellent supercapacity with a large gravimetric capacitance and great cycling stability. 相似文献
976.
Endoplasmic Reticulum–Targeted Fluorescent Nanodot with Large Stokes Shift for Vesicular Transport Monitoring and Long‐Term Bioimaging
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Leilei Shi Xihui Gao Wangzhang Yuan Li Xu Hongping Deng Chenwei Wu Jiapei Yang Xin Jin Chuan Zhang Xinyuan Zhu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(25)
Herein, a highly stable aggregation‐induced emission (AIE) fluorescent nanodot assembled by an amphiphilic quinoxalinone derivative‐peptide conjugate, namely Quino‐1‐Fmoc‐RACR (also termed as Q1‐PEP), which exhibits large Stokes shift and an endoplasmic reticulum (ER)‐targeting capacity for bioimaging is reported. It is found that the resulting nanodot can effectively enter the ER with high fluorescent emission. As the ER is mainly involved in the transport of synthesized proteins in vesicles to the Golgi or lysosomes, the Q1‐PEP nanodot with ER‐targeting capacity can be used to monitor vesicular transport inside the cells. Compared to conventional fluorescent dyes with small Stokes shifts, the self‐assembled fluorescent nanodot shows superior resistance to photobleaching and aggregation‐induced fluorescence quenching, and elimination of the spectra overlap with autofluorescence of biosubstrate owning to their AIE‐active and red fluorescence emission characteristics. All these optical properties make the fluorescent nanodot suitable for noninvasive and long‐term imaging both in vitro and in vivo. 相似文献
977.
Yuping Jia Xiaojuan Sun Zhiming Shi Ke Jiang Henan Liu Jianwei Ben Dabing Li 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(26)
Silicon carbide (SiC) with epitaxial graphene (EG/SiC) shows a great potential in the applications of electronic and photoelectric devices. The performance of devices is primarily dependent on the interfacial heterojunction between graphene and SiC. Here, the band structure of the EG/SiC heterojunction is experimentally investigated by Kelvin probe force microscopy. The dependence of the barrier height at the EG/SiC heterojunction to the initial surface state of SiC is revealed. Both the barrier height and band bending tendency of the heterojunction can be modulated by controlling the surface state of SiC, leading to the tuned carrier transport behavior at the EG/SiC interface. The barrier height at the EG/SiC(000‐1) interface is almost ten times that of the EG/SiC(0001) interface. As a result, the amount of carrier transport at the EG/SiC(000‐1) interface is about ten times that of the EG/SiC(0001) interface. These results offer insights into the carrier transport behavior at the EG/SiC heterojunction by controlling the initial surface state of SiC, and this strategy can be extended in all devices with graphene as the top layer. 相似文献
978.
Nanoconfined Nickel@Carbon Core–Shell Cocatalyst Promoting Highly Efficient Visible‐Light Photocatalytic H2 Production
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Ke Zhang Jingrun Ran Bicheng Zhu Huanxin Ju Jiaguo Yu Li Song Shi‐Zhang Qiao 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(38)
The realization of large‐scale solar hydrogen (H2) production relies on the development of high‐performance and low‐cost photocatalysts driven by sunlight. Recently, cocatalysts have demonstrated immense potential in enhancing the activity and stability of photocatalysts. Hence, the rational design of highly active and inexpensive cocatalysts is of great significance. Here, a facile method is reported to synthesize Ni@C core–shell nanoparticles as a highly active cocatalyst. After merging Ni@C cocatalyst with CdS nanorod (NR), a tremendously enhanced visible‐light photocatalytic H2‐production performance of 76.1 mmol g?1 h?1 is achieved, accompanied with an outstanding quantum efficiency of 31.2% at 420 nm. The state‐of‐art characterizations (e.g., synchrotron‐based X‐ray absorption near edge structure) and theoretical calculations strongly support the presence of pronounced nanoconfinement effect in Ni@C core–shell nanoparticles, which leads to controlled Ni core size, intimate interfacial contact and rapid charge transfer, optimized electronic structure, and protection against chemical corrosion. Hence, the combination of nanoconfined Ni@C with CdS nanorod leads to significantly improved photocatalytic activity and stability. This work not only for the first time demonstrates the great potential of using highly active and inexpensive Ni@C core–shell structure to replace expensive Pt in photocatalysis but also opens new avenues for synthesizing cocatalyst/photocatalyst hybridized systems with excellent performance by introducing nanoconfinement effect. 相似文献
979.
3D Mesostructures: Fabrication and Deformation of 3D Multilayered Kirigami Microstructures (Small 11/2018)
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980.
Neng Li Shuai Huang Guodong Zhang Renyao Qin Wei Liu Huaping Xiong Gongqi Shi Jon Blackburn 《材料科学技术学报》2019,35(2):242-269
Recent efforts and advances in additive manufacturing (AM) on different types of new materials are presented and reviewed. Special attention is paid to the material design of cladding layers, the choice of feedstock materials, the metallurgical behavior and synthesis principle during the AM process, and the resulted microstructures and properties, as well as the relationship between these factors. Thereafter, the trend of development in the future is forecasted, including: Effects of the particles size and size distribution of powders; Approaches for producing fine microstructures; Opportunities for creating new materials by AM; Wide applications in reconditioning of damaged components; Challenges for deep understanding and applications of the AMed new materials. The idea of “Develop Materials” or “Create Materials” by AM is highlighted, but a series of scientific, technological and engineering problems remain to be solved in future. 相似文献