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141.
Xujin Qin Jianlei Han Dong Yang Wenjie Chen Tonghan Zhao Xue Jin Peipei Guo Pengfei Duan 《中国化学快报》1990,30(11):1923-1926
Triplet-triplet annihilation based photon upconversion (TTA-UC) were constructed successfully by chiral self-assembly strategy.Enhanced TTA-UC could be obtained in the racemic assemblies compared with the homochiral assemblies. 相似文献
142.
143.
Study on the p-type QWIP-LED device 总被引:1,自引:1,他引:0
A p-type quantum well infrared photodetector (QWIP) integrated with a light-emitting diode (LED) (named QWIP-LED) was fabricated
and studied. The infrared photo-response spectrum was obtained from the device resistance variation and the near-infrared
photo-emission intensity variation. A good agreement between these two spectra was observed, which demonstrates that the long-wavelength
infrared radiation around 7.5 μm has been transferred to the near-infrared light at 0.8 μm by the photo-electronic process
in the QWIP-LED structure. Moreover, the experimentally observed infrared response wavelength is in good agreement with the
theoretical calculation value of 7.7 μm. The results on the upconversion of the infrared radiation will be very useful for
the new infrared focal plane array technology. 相似文献
144.
Shiqing Xu Guonian Wang Shixun Dai Junjie Zhang Lili Hu Zhonghong Jiang 《Journal of solid state chemistry》2004,177(9):3127-3130
The green and red upconversion luminescence of Er3+ in lead chloride tellurite glasses excited at 980 nm is investigated. Three intense emission bands centered at 530, 545, and 658 nm corresponding to the transitions 4S3/2→4I15/2, 2H11/2→4I15/2 and 4F9/2→4I15/2, respectively, were simultaneously observed at room temperature. With increasing PbCl2 content, the intensity of green (530 nm) emissions increase slightly, while the green (545 nm) and red (658 nm) emissions increase significantly. The results indicate that PbCl2 has more influence on the green (545 nm) and red (658 nm) emissions than the green (530 nm) emission. The dependence of upconversion intensities on excitation power and possible upconversion mechanisms are discussed and evaluated. 相似文献
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147.
稀土掺杂上转换纳米粒子(RED-UCNPs)作为一种新型高效的上转换发光纳米材料,具有反斯托克斯位移大,发射光谱窄、发光寿命长、材料毒性低等优点,已成为荧光标记、光动力学治疗、生物成像和构建生物传感器等领域的研究热点。然而,目前广泛使用的溶剂热法合成的RED-UCNPs生物相容性和亲水性差,而且不具备与生物分子之间相偶联的活性基团,因此对RED-UCNPs进行表面功能化修饰就显得格外重要。本文重点综述了RED-UCNPs的表面功能化修饰的类型及其应用现状,为RED-UCNPs的进一步研究开发和应用提供思路和参考依据。 相似文献
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149.
This paper studies the upconversion luminescence phenomenon of the Ho,Yb co-doped oxyfluoride vitroceramics. There is one group of strong upconversion luminescence lines positioned at 536.5nm, 18639cm-1; 540.5nm, 18501cm-1; 544.0nm, 18399cm-1, which is easily identified as the transitions of 5S2→5I8. There are other splendid upconversion luminescence lines, which are 5S2→5I7,5F5→5I8,5G6→5I8, (5G3G)5 →5I8,(3F3H5G)4→5I7,5G4→5I8 and (5G3H)5→5I8. It is also found that an interesting kind of upconversion cooperative radiation fluorescence comes from a kind of coupling state of clusters consisting of two Yb3+ ions. 相似文献
150.
980nm红外激发下氟氧化物中Er3+的上转换可见发光 总被引:2,自引:2,他引:0
制备了掺杂Er3+的氟氧化物(10ZrF4-10PbF2-10NaF-5Na2O-60SiO2)材料,测量了样品的吸收谱、上转换荧光发射谱和上转换发光强度与激光泵浦功率的对数关系.分析了Er3+的上转换可见发光机制,证实了在980nmLD的激发下,Er3+在402nm、449nm蓝光波段和520nm、551nm绿光波段的上转换荧光发射来自于4f电子的2H9/2、4F5/2、4S3/2、2H11/2激发态到基态4I15/2的跃迁,给出了2H9/2→4I15/2、4F5/2→4I15/2蓝光三光子激发态吸收(ESA)和4S3/2→4I15/2、2H11/2→4I15/2绿光双光子激发态吸收(ESA)的上转换发光机制. 相似文献