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Lubick N 《Environmental science & technology》2007,41(10):3400-3401
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Plasmonic enhancement of molecular fluorescence 总被引:2,自引:0,他引:2
Metallic nanoparticles are known to dramatically modify the spontaneous emission of nearby fluorescent molecules and materials. Here we examine the role of the nanoparticle plasmon resonance energy and nanoparticle scattering cross section on the fluorescence enhancement of adjacent indocyanine green (ICG) dye molecules. We find that enhancement of the molecular fluorescence by more than a factor of 50 can be achieved for ICG next to a nanoparticle with a large scattering cross section and a plasmon resonance frequency corresponding to the emission frequency of the molecule. 相似文献
77.
Makoto Yamaguchi Shoichi Shichimiya Shinji Ishibe Naomi Furuse Masahiro Kobayashi Toshihiro Suzuki Junichi Shimizu Susumu Nishiki 《Electrical Engineering in Japan》2000,131(3):34-42
New zinc oxide elements with a varistor voltage about twice that of conventional ones have been developed by reducing the ZnO grain size with a new additive, making it possible to halve the series number of elements in metal oxide surge arresters. The advanced arresters with these elements for GIS are smaller in volume by 40 to 60% compared with conventional ones. These advanced MOAs increase the flexibility in positioning MOAs and optimizing the GIS layout. This paper describes the performance of the new elements, the specification and construction of the advanced MOAs, and the results of typical evaluation tests. © 2000 Scripta Technica, Electr Eng Jpn, 131(3): 34–42, 2000 相似文献
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Masanobu Yoshida Toshihiro Takahashi Masayuki Hikita Hiroyuki Watanabe Naomi Hashimoto Hitoshi Okubo 《Electrical Engineering in Japan》1999,129(4):58-65
We observed current pulse waveforms of partial discharge (PD) in SF6 gas so as to investigate the PD mechanism. We also measured light intensity and light emission image of PD simultaneously under different conditions of applies voltage and SF6 gas pressure. From these experiments, we found that the “double-peak current waveform” appeared at high pressure and high voltage conditions. We also analyzed the mutual correlation of waveforms between a single current and the light emission. Moreover, we obtained experimental evidence of filmentlike light image appearing at the PD tip under the same condition with double-peak current waveform. From the electric field analysis around the needle electrode tip, we believe that the filamentlike light image expands beyond the critical electric field of SF6 gas. Thus, we concluded that these current waveforms with double peaks showed evidence of leader-type PD, leading to breakdown. Finally, we could point out that leader-type PD should be distinguished and measured for the diagnosis of GIS insulation performance. © 1999 Scripta Technica, Electr Eng Jpn, 129(4): 58–65, 1999 相似文献
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Tomoko Hirayama Naomi Yamaguchi Noriaki Hishida Hiroshi Yabe 《Tribology International》2009,42(5):675-681
Optimization of groove dimensions in herringbone-grooved journal bearings is discussed in this paper with aims to design precision spindles with improved run-out characteristics. An evaluation index to represent the magnitude of the amplitude of repeatable run-out is firstly introduced and the groove design parameters are theoretically discussed to minimize the index value with taking the stable operation condition of the bearing into account. The comprehensive parameter research reveals a guideline for the design of the groove configuration for good run-out characteristics. Experiments with a shaft with grooves designed along the proposed guideline show that the amplitude of repeatable run-out reduces to about half of that of a bearing with currently designed groove configurations, thus confirming validity of the above guideline. 相似文献
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