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61.
M. Benatsou B. Capoen M. Bouazaoui W. Tchana J.P. Vilcot 《Journal of Sol-Gel Science and Technology》1998,13(1-3):529-533
Er3+ doped-aluminosilicate thin films were prepared on silica and silica/Si substrates by the sol-gel process and dip-coating. The sol-gel aluminosilicate planar waveguides were prepared from silicon and aluminium alkoxides. Their structural characterization has been carried out by Raman spectroscopy, Atomic Force and Scanning Electron Microscopies. The results indicated that these films present an amorphous structure until an annealing temperature of 900°C, while at temperatures higher than 1000°C, crystallization occurs. An estimate of microcrystallite sizes using Raman spectroscopy is given, which agrees with data from scanning electron microscopy. The optical properties have been investigated by Fluorescence spectroscopy in the visible region. 相似文献
62.
Er3+,Ho3+和Tm3+在硫氧化钆中的余辉发光 总被引:1,自引:0,他引:1
The new Er^3 , Ho^3 and Tm^3 doped gadolinium oxysulfide phosphors with the long afterglow emission were synthesized by solid-state reaction method. The synthesized phosphors were characterized by X-ray diffraction. The excitation and photolumineseenee spectra, afterglow spectra and afterglow decay curve were examined by fluorescence spectroscopy. The afterglow spectra of Gd2O2S:Er^3 , Mg, Ti showed typical transitions of Er^3 at 528(2H11/2→4I15/2), 548 (^4S3/2 →^4I15/2) and 669 nm (^4F9/2→^4I15/2). In the afterglow spectra of Gd2O2S: Ho^3 , Mg, Ti,typical transitions of Ho^3 at 546 nm (^5S2→^5I8), 651 and 661 nm (^2F5→^5I8) were observed. In Gd2O2S:Tm^3 , Mg,Ti, the afterglow emission at 800 nm (^1G4→^3H5) of Tm^3 was seen. The meehnism and model of afterglow energy transfer were proposed. 相似文献
63.
针对传统云水含量传感器体积大,功耗大等问题,本文基于可调谐半导体激光器吸收光谱技术,研制了一种云水含量检测系统.采用1 368.6nm分布式反馈半导体激光器作为检测光源,设计了基于TLC7528芯片的正交锁相放大器,提高了测量的稳定性和抑制噪声的能力;单板实现了激光器驱动、谐波信号处理、浓度反演功能.系统在不同浓度,不同温度下进行在线检测,实验结果表明,系统响应时间为10s左右,水含量在0~16g/m3范围内误差小于5%,在-55^+60℃条件下可正常工作.该系统体积小,检测精度高,响应速度快,性能不受温度影响,很好地满足了机载云层探测需要. 相似文献
64.
65.
Optical absorption of Er3+ ion in Er(NO3)3·5H2O, NH4NO3, Mg(NO3)2·6H2O, KNO3 and NaNO3 complexes has been studied. The second derivative spectra of these Er3+ complexes exhibited splittings in the4
I
9/2,4
F
9/2,4
F
7/2,4
F
5/2 and2
H
9/2 levels. These splittings have been tentatively explained as due to a cubic crystalline field. The partial derivatives for
Er3+ ion have been calculated in terms of Racah (E
k
) parameters. The results of a least squares fit of the energy levels and oscillator strengths of the bands are reported in
terms of interaction parameters and Judd-Ofelt parameters. Radiative transition probabilities for various fluorescence levels
are theoretically estimated. The lifetime of the4
G
11/2 level is found to be lowest in all nitrate complexes. 相似文献
66.
I. D. Phillips A. Gloag D. G. Moodie N. J. Doran I. Bennion A. D. Ellis 《Optics Communications》1998,150(1-6):101-105
A single electroabsorption modulator was used to demultiplex a 10 Gbit/s channel from a 40 Gbit/s OTDM data stream, whilst simultaneously recovering the 10 GHz electrical clock. This was achieved using a new bi-directional operation of the EA modulator, combined with a simple phase-locked loop feedback circuit. Excellent system performance was achieved, indicating that operation up to and beyond 100 Gbit/s is possible using current technology. 相似文献
67.
On a New Observed Dimorphism of BaCoEr2O5 Single crystals of BaCoEr2O5 were prepared by CO2-LASER technique under N2-atmosphere and investigated by X-ray single crystal methods. It crystallizes with orthorhombic symmetry, space group D-Pnma (a = 12.2787, b = 5.6826, c = 7.0344 Å; Z = 4). The so far unknown crystal structure of BaCoEr2O5 belongs to the BaCuLn2O5 type forming the dimorphic substance to the previously described Ni type of BaCoEr2O5. 相似文献
68.
电感耦合等离子体质谱法测定高纯氧化铒中14种稀土杂质 总被引:6,自引:0,他引:6
用电感耦合等离子体质谱研究了直接测定99.999%Er2O3中14个稀土杂质的含量。采用基体匹配法扣除Er和Ho和Tm元素的基体峰背景干扰,选择同位素Er^162为内标,可显著提高测量精度和准确度。 相似文献
69.
在水溶液中合成了标题配合物,其化学式为Er(Met)2(ClO4)3·4.5H2O(Met为蛋氨酸).研究了配合物的红外光谱.用X射线单晶衍射法测定了配合物的晶体结构,结果表明,其结构式为[Er2(DL-Met)4·8H2O]·(ClO4)6·H2O.属单斜晶系,空间群为P21/n,晶胞参数为:a=13.846(5)A,b=21.794(7)A,C=19.131(5),β=90.51(3)°,V=5772.84(3)3,Z=4.每两个Er原子之间通过四个蛋氨酸的羧基桥相连而形成双核配合物.两对对位的蛋氨酸中,其中一个为L型,而另一个为D型.每个Er原子还与四个水分子配位,其配位数为8.对于每个双核离子而言,其配位多面体由两个四方反棱柱体组成. 相似文献
70.
利用倍频电路产生十路不同频率的相干信号,通过滤波、移相、幅度调整、加法器、乘法器等电路可实现用多路正弦信号做波形合成、两路信号的同向振动合成,李萨茹图形、调幅波等实验及演示。 相似文献