TN25 2001053332LAPOSH光纤的研制及其8×10 Gb/s系统试验=Disign and manufacturing of LAPOSH fiber and its 8×10 Gb/s transmission test[刊,中]/程铭,施璐(武汉邮电科学研究院系统部.湖北,武汉(430074)),黄彦彬,王铁军,...TN25 2001053332LAPOSH光纤的研制及其8×10 Gb/s系统试验=Disign and manufacturing of LAPOSH fiber and its 8×10 Gb/s transmission test[刊,中]/程铭,施璐(武汉邮电科学研究院系统部.湖北,武汉(430074)),黄彦彬,王铁军,张雁翔,漆启年(武汉长飞光纤光缆有限公司.湖北,武汉(430073))//光通信技术.—2000,24(3).展开更多
O482．31 2005053924 BaFBr:Eu2+中Al3+的最佳掺杂浓度研究=Investigation of optimum of Al3+-doped in BaFBr:Eu2+ by electron paramagnetic resonance[刊,中]／刘永胜(天津理工大学理 学院．天津(300191)),余华∥光电子·激光．...O482．31 2005053924 BaFBr:Eu2+中Al3+的最佳掺杂浓度研究=Investigation of optimum of Al3+-doped in BaFBr:Eu2+ by electron paramagnetic resonance[刊,中]／刘永胜(天津理工大学理 学院．天津(300191)),余华∥光电子·激光．-2005,16 (4)．-444-446,453 把Al3+掺入BaFBr:Eu2+中,取代了其中部分Ba2+, 这些金属离子将影响到色心F(Br-),使其激发能变小。 通过电子顺磁共振(EPR)谱研究了掺杂Al3+的量值对光 激励发光强度的影响,确定光激励发光强度最大时的最佳 掺杂比例为0．015％。对这一结果从色心的形成机理上进 行了讨论,指出掺杂量不是越多越好,过多的掺杂Al3+能 导致俘获电子的空位发生聚集,俘获电子的能力变弱,使 光激励发光强度降低。图2表1参5(严寒)展开更多
Cr-doped ZnO thin films are prepared on glass substrates by the magnetron sputtering technique. An X-ray diffraction (XRD) is used to analyze the structural properties of the thin films. It indicates that all the thin...Cr-doped ZnO thin films are prepared on glass substrates by the magnetron sputtering technique. An X-ray diffraction (XRD) is used to analyze the structural properties of the thin films. It indicates that all the thin films have a preferential c-axis orientation. The peak position of the (002) plane shifts to the higher 2θ value, and the peak intensity decreases with the increase of Cr doping. The results of the scanning electron microscopy (SEM) show that the surface morphology becomes loose with the increase of Cr doping. Besides, it is found from the photoluminescence (PL) measurement at room temperature that the ultraviolet emission peak and green emission band are located at 375 nm and 520 nm, respectively, and both intensities of them decrease with the increase of the Cr doping concentration, while the band gap of the ultraviolet emission shifts to the lower wavelength. The experimental results confirm that the optimal Cr doping concentration is 2 at. %.展开更多
Eu^(3+)-doped ZnMoO_4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu^(3+)doping on the phase structure and photoluminescence(PL) properties of ZnMoO_4 were investigat...Eu^(3+)-doped ZnMoO_4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu^(3+)doping on the phase structure and photoluminescence(PL) properties of ZnMoO_4 were investigated. The result showed that the introduction of Eu^(3+) could lead to phase transition of ZnMoO_4. With the increase of Eu^(3+)doping amount, β-ZnMoO_4 was transformed to a phase gradually, which led to different photoluminescence performances. The optimized doping concentration of Eu^(3+) was 6 mol% for the highest emission intensity at 615 nm. Its CIE chromaticity coordinates were(0.667, 0.331), which were very close to the values of standard chromaticity(0.67, 0.33) for National Television Standards Committee(NTSC) system.Therefore, Eu^(3+)-doped ZnMoO_4 is considered to be a promising red-emitting phosphor for white LED applications.展开更多
We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La_(2.x)Ce_xCuO_(4±δ) thin films as a function of Ce doping and oxygen content in the magnetic field up to 14 T. A cross...We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La_(2.x)Ce_xCuO_(4±δ) thin films as a function of Ce doping and oxygen content in the magnetic field up to 14 T. A crossover from negative to positive magnetoresistance occurs between the doping level x = 0.07 and 0.08. Above x = 0.08, the positive magnetoresistance effect appears, and is almost indiscernible at x = 0.15. By tuning the oxygen content, the as-grown samples show negative magnetoresistance effect, whereas the optimally annealed ones display positive magnetoresistance effect at the doping level x = 0.15. Intriguingly, a linear-field dependence of in-plane magnetoresistance is observed at the underdoping level x = 0.06, the optimal doping level x = 0.1 and slightly overdoping level x = 0.11. These anomalies of in-plane magnetoresistance may be related to the intrinsic inhomogeneity in the cuprates, which is discussed in the framework of network model.展开更多
Yellow-green-emitting Sr Si2O2N2:Eu2+phosphors were synthesized with Sr2Si O4:Eu2+as precursor.The effects of flux and the concentration of Eu2+on the crystal structure and luminescent properties of the phosphors were...Yellow-green-emitting Sr Si2O2N2:Eu2+phosphors were synthesized with Sr2Si O4:Eu2+as precursor.The effects of flux and the concentration of Eu2+on the crystal structure and luminescent properties of the phosphors were investigated.Results suggested that the optimal content of flux Na2CO3 was 1 wt%and the optimal doping concentration of Eu2+was 0.05 mol.The emission spectra showed the most intense peaks located at 535 nm which corresponded to the 4f65d→4f7 transition of Eu2+.The excitation spectra showed that these phosphors could be effectively excited by near-ultraviolet and blue light,whichwas consistent with the widely applied output wavelengths of near-ultraviolet and blue-white light-emitting diode(LED)chips.When the influence of flux on the luminescent properties of Sr Si2O2N2:Eu2+phosphor was analyzed,the X-ray diffraction(XRD)patterns indicated that the flux could help the crystallization of the phosphors.No other phases except the triclinic structure of Sr Si2O2N2 were formed.The thermal stability and the emission intensity of synthesized Sr Si2O2N2:Eu2+phosphor were examined and compared with commercial YAG yellow phosphors.All results indicate that the yellow-green-emitting phosphor is a suitable candidate for the fabrication of white LEDs.展开更多
文摘TN25 2001053332LAPOSH光纤的研制及其8×10 Gb/s系统试验=Disign and manufacturing of LAPOSH fiber and its 8×10 Gb/s transmission test[刊,中]/程铭,施璐(武汉邮电科学研究院系统部.湖北,武汉(430074)),黄彦彬,王铁军,张雁翔,漆启年(武汉长飞光纤光缆有限公司.湖北,武汉(430073))//光通信技术.—2000,24(3).
文摘O482．31 2005053924 BaFBr:Eu2+中Al3+的最佳掺杂浓度研究=Investigation of optimum of Al3+-doped in BaFBr:Eu2+ by electron paramagnetic resonance[刊,中]／刘永胜(天津理工大学理 学院．天津(300191)),余华∥光电子·激光．-2005,16 (4)．-444-446,453 把Al3+掺入BaFBr:Eu2+中,取代了其中部分Ba2+, 这些金属离子将影响到色心F(Br-),使其激发能变小。 通过电子顺磁共振(EPR)谱研究了掺杂Al3+的量值对光 激励发光强度的影响,确定光激励发光强度最大时的最佳 掺杂比例为0．015％。对这一结果从色心的形成机理上进 行了讨论,指出掺杂量不是越多越好,过多的掺杂Al3+能 导致俘获电子的空位发生聚集,俘获电子的能力变弱,使 光激励发光强度降低。图2表1参5(严寒)
基金supported by Tianjin Natural Science Foundation (No.06YFJZJC00100)
文摘Cr-doped ZnO thin films are prepared on glass substrates by the magnetron sputtering technique. An X-ray diffraction (XRD) is used to analyze the structural properties of the thin films. It indicates that all the thin films have a preferential c-axis orientation. The peak position of the (002) plane shifts to the higher 2θ value, and the peak intensity decreases with the increase of Cr doping. The results of the scanning electron microscopy (SEM) show that the surface morphology becomes loose with the increase of Cr doping. Besides, it is found from the photoluminescence (PL) measurement at room temperature that the ultraviolet emission peak and green emission band are located at 375 nm and 520 nm, respectively, and both intensities of them decrease with the increase of the Cr doping concentration, while the band gap of the ultraviolet emission shifts to the lower wavelength. The experimental results confirm that the optimal Cr doping concentration is 2 at. %.
文摘Eu^(3+)-doped ZnMoO_4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu^(3+)doping on the phase structure and photoluminescence(PL) properties of ZnMoO_4 were investigated. The result showed that the introduction of Eu^(3+) could lead to phase transition of ZnMoO_4. With the increase of Eu^(3+)doping amount, β-ZnMoO_4 was transformed to a phase gradually, which led to different photoluminescence performances. The optimized doping concentration of Eu^(3+) was 6 mol% for the highest emission intensity at 615 nm. Its CIE chromaticity coordinates were(0.667, 0.331), which were very close to the values of standard chromaticity(0.67, 0.33) for National Television Standards Committee(NTSC) system.Therefore, Eu^(3+)-doped ZnMoO_4 is considered to be a promising red-emitting phosphor for white LED applications.
基金supported by the National Key Basic Research Program of China (Grant Nos. 2015CB921000, and 2016YFA0300301)the National Natural Science Foundation of China (Grant Nos. 11674374, and 11474338)the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH008)
文摘We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La_(2.x)Ce_xCuO_(4±δ) thin films as a function of Ce doping and oxygen content in the magnetic field up to 14 T. A crossover from negative to positive magnetoresistance occurs between the doping level x = 0.07 and 0.08. Above x = 0.08, the positive magnetoresistance effect appears, and is almost indiscernible at x = 0.15. By tuning the oxygen content, the as-grown samples show negative magnetoresistance effect, whereas the optimally annealed ones display positive magnetoresistance effect at the doping level x = 0.15. Intriguingly, a linear-field dependence of in-plane magnetoresistance is observed at the underdoping level x = 0.06, the optimal doping level x = 0.1 and slightly overdoping level x = 0.11. These anomalies of in-plane magnetoresistance may be related to the intrinsic inhomogeneity in the cuprates, which is discussed in the framework of network model.
基金supported by the National Natural Science Foundation of China(Grant No.11204258)the National Science Foundation for Distinguished Young Scholars of Fujian Province(Grant No.2012J06024)+3 种基金the Program for New Century Excellent Talents in University of Fujian Province(Grant No.ZA14228)the Outstanding Young Scientific Research Personnel Training Plan in Colleges and Universities of Fujian Province(Grant No.JA13229)the Science and Technology Plan of Xiamen City(Grant No.3502Z20123040)the Ministry of Education in China Project of Humanities and Social Sciences(Grant No.11YJC820135)
文摘Yellow-green-emitting Sr Si2O2N2:Eu2+phosphors were synthesized with Sr2Si O4:Eu2+as precursor.The effects of flux and the concentration of Eu2+on the crystal structure and luminescent properties of the phosphors were investigated.Results suggested that the optimal content of flux Na2CO3 was 1 wt%and the optimal doping concentration of Eu2+was 0.05 mol.The emission spectra showed the most intense peaks located at 535 nm which corresponded to the 4f65d→4f7 transition of Eu2+.The excitation spectra showed that these phosphors could be effectively excited by near-ultraviolet and blue light,whichwas consistent with the widely applied output wavelengths of near-ultraviolet and blue-white light-emitting diode(LED)chips.When the influence of flux on the luminescent properties of Sr Si2O2N2:Eu2+phosphor was analyzed,the X-ray diffraction(XRD)patterns indicated that the flux could help the crystallization of the phosphors.No other phases except the triclinic structure of Sr Si2O2N2 were formed.The thermal stability and the emission intensity of synthesized Sr Si2O2N2:Eu2+phosphor were examined and compared with commercial YAG yellow phosphors.All results indicate that the yellow-green-emitting phosphor is a suitable candidate for the fabrication of white LEDs.
