排序方式: 共有11条查询结果,搜索用时 31 毫秒
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A general method for large-scale fabrication of Cu nanoislands/dragonfly wing SERS flexible substrates 下载免费PDF全文
Noble metal nanorough surfaces that support strong surface-enhanced Raman scattering(SERS) is widely applied in the practical detection of organic molecules. A low-cost, large-area, and environment-friendly SERS-active substrate was acquired by sputtering inexpensive copper(Cu) on natural dragonfly wing(DW) with an easily controlled way of magnetron sputtering. By controlling the sputtering time of the fabrication of Cu on the DW, the performance of the SERS substrates was greatly improved. The SERS-active substrates, obtained at the optimal sputtering time(50 min),showed a low detection limit(10~(-6)M) to 4-aminothiophenol(4-ATP), a high average enhancement factor(EF, 1.98 × 10~4),excellent signal uniformity, and good reproducibility. In addition, the results of the 3D finite-difference time-domain(3 DFDTD) simulation illustrated that the SERS-active substrates provided high-density "hot spots", leading to a large SERS enhancement. 相似文献
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Hongwen Cao 《中国物理 B》2022,31(3):37803-037803
Wheat leaves with natural microstructures as substrates were covered by the silver nanoislands by magnetron to prepare a low-cost, environment-friendly and mass production surface-enhanced fluorescence (SEF) substrate (Ag-WL substrate). The best SEF substrate was selected by repeatly certifying the fluorescence intensity of 10-5 M Rhodamine B (RB) and 10-5 M Rhodamine 6G (R6G) aqueous solutions. The abundant semi-spherical protrusions and flake-like structures on the surface of the Ag-WL substrate produce high-density hot spots, which provides a new and simple idea for the preparation of biomimetic materials. The results of 3D finite-different time-domain (FDTD) simulation show that the nanoisland gap of semi-spherical protrusions and flake-like structures has produced rich hotspots. By adjusting the time of magnetron sputtering, the enhancement factor (EF) was as high as 839 times, relative standard deviation (RSD) reached as low as 10.7%, and the substrate was very stable and repeatable, which shows that Ag-WL substrate is trustworthy. Moreover, semi-spherical protrusions provide stronger surface-enhanced Raman scattering (SERS) effects compared to flake-like structure. What is more surprising is that the detection limit of the substrate for toxic substance crystal violet (CV) is as low as 10-10 M. 相似文献
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光学薄膜的相位变化与特点 总被引:1,自引:0,他引:1
从薄膜的导纳入手,分析了多层薄膜的相位特点和波长与相位的变化关系。计算了高反薄膜的相位变化,分析了光学薄膜的相位对光学器件的影响。 相似文献
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A novel natural surface-enhanced fluorescence system based on reed leaf as substrate for crystal violet trace detection 下载免费PDF全文
Hui-Ju Cao 《中国物理 B》2022,31(10):107801-107801
The preparation of surface-enhanced fluorescence (SEF) substrates is often influenced by experimental strategies and factors such as the morphology and size of the nanostructures. In this study, using the natural reed leaves (RLs) without any special pretreatment as the substrate, metal silver is modified by magnetron sputtering technology to prepare a stable and efficient SEF system. The abundant “hedgehog-like”protrusions on the RL substrate surface can generate high-density “hot spots”, thus enhancement factor (EF) is enhanced up to 3345 times. The stability and reproducibility are verified in many measurements. The contribution of the intervention of silver nanostructure to the radiation attenuation process of fluorescent molecules is analyzed with the aid of Jablonski diagrams. Three-dimensional (3D) finite difference time domain (FDTD) simulates the spatial electric field and “hot spots”distribution of the substrate. The “hedgehog-like”protrusion structure generates multiple “hot spots”, which produce an excellent local surface plasmon resonance (LSPR) effect and provide higher fluorescence signal. Finally, RL/Ag-35 substrate is used to detect crystal violet (CV), and the detection limit is as low as 10-13 M. This “hedgehog-like”SEF substrate provides a new strategy for the trace detection of CV, which has a good practical application value. 相似文献
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飞秒激光器的相位薄膜 总被引:1,自引:1,他引:0
论述了飞秒激光器的相位补偿特点,讨论了采用位薄膜作为补偿晶体的色散和相位自调制的飞秒激光器,并对相位薄膜进行了理论设计。 相似文献
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硅,锗片的激光损伤及加固研究 总被引:3,自引:0,他引:3
利用YAG脉冲激光在二种脉宽下(10ns、250μs),对Si、Ge片进行了损伤研究,分别给出了表面损伤机制,并利用镀金风石膜、介质膜和激光预辐照进行加固,讨论了加固效果。 相似文献
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An effective surface-enhanced Raman scattering template based on gold nanoparticle/silicon nanowire arrays 下载免费PDF全文
A large-scale Si nanowire array (SiNWA) is fabricated with gold (Au) nanoparticles by simple metal-assisted chemical etching and metal reduction processes. The three-dimensional nanostructured Au/SiNWA is evaluated as an active substrate for surface-enhanced Raman scattering (SERS). The results show that the detection limit for rhodamine 6G is as low as 10-7 M, and the Raman enhancement factor is as large as 105 with a relative standard deviation of less than 25%. After the calibration of the Raman peak intensifies of rhodamine 6G and thiram, organic molecules could be quantitatively detected. These results indicate that Au/SiNWA is a promising SERS-active substrate for the detection of biomolecules present in low concentrations. Our findings are an important advance in SERS substrates to allow fast and quantitative detection of trace organic contaminants. 相似文献