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991.
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
992.
以硝酸锌和六次甲基四胺为原料,水为溶剂,采用低温水热法制备出具有优异光催化性能的六方纤锌矿结构ZnO微纳米棒,并研究了合成过程中磁力搅拌及原料溶液浓度对制备产物形貌及光催化性能的影响,建立了其光催化降解甲基橙的动力学方程。结果表明,搅拌条件下制备的产物为纵向多孔的棒状ZnO,无搅拌条件下制备的产物为实心ZnO纳米棒.优选出的硝酸锌和六次甲基四胺浓度均为0.025mol/L。相比于实心ZnO纳米棒,纵向多孔的棒状ZnO具有更优异的光催化性能,在紫外光照射20min后,对甲基橙的降解率达到100%。通过动力学模型拟合发现,纵向多孔的棒状ZnO具有更大的催化速率常数(0.2942 min~(-1)),是实心ZnO纳米棒催化速率常数(0.1306min~(-1))的2.25倍。 相似文献
993.
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995.
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)
996.
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
997.
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
998.
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
999.
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
1000.
3D Mesostructures: Fabrication and Deformation of 3D Multilayered Kirigami Microstructures (Small 11/2018)
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