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51.
Alexander A. Kaminskii Ludmila Li Andre V. Butashin Vladimir S. Mironov Alexsei A. Pavlyuk Sergey N. Bagayev Ken-ichi Ueda 《Optical Review》1997,4(2):309-315
Monoclinic KY(WO4)2:Pr3+, Tm3+:KY(WO4)2:Er3+, Yb3+ single crystals are grown by low-gradient Czochralski technique. Stimulated emission at 1.0223μm wavelength in the new lasing 1D2→3F3 channel of Pr3+ ions in KY(WO4)2 at room temperature under Xe-flashlamp pumping is excited. Full sets of Stark-level energies for Pr3+ ions in KY(WO4)2 and KGd(WO4)2 crystals at 77 K are determined. 4f2-4f2 intensity-transitions for the KY(WO4)2:Pr3+ are analyzed preliminarily. All observed at present and earlier one-micron Pr3+-ion, induced transitions in the 1D2→3F3 and 1D2→3F4 channels are identified. In yttrium and gadolinium sensitized-tungstates a two-micron (3H4→3H6) low-threshold generation of Tm3+ ions at cryogenic temperatures is achieved.All authors cooperate with the Joint Open Laboratory for Laser Crystals and Precise Laser Systems at the Institute of Crystallography and Institute of Laser Physics, Russian Academy of Sciences. 相似文献
52.
加注稀土元素铒改善轴承表面性能的研究 总被引:2,自引:0,他引:2
在Mo^++N^+注入模式的基础上,应用电子能谱、卢瑟福背散射谱、扫描电子显微镜和MHK-500型摩擦磨损试验机等研究了加注稀土元素铒正离子Er^+对轴承表面摩擦学性能和耐蚀性能的影响。结果表明,在合理配置Mo^+、N^+、Er^+之能量和剂量的情况下,加注Er^+既能更好地改善轴承的表面性能,又能使重离子的强韧化效果提高2-4倍以上,表明MO^++N^++Er^+注入模式是一种具有良好应用前景的 相似文献
53.
采用凝胶法分别制备出4.5ZnO-5.5Al2O3-90SiO2(ZAS)以及ZAS[DK]:RE3+ (RE=Eu,Tb,Ce) 透明微晶玻璃。利用X射线衍射仪(XRD)、透射电子显微镜(TEM)和荧光光谱仪(PL)等测试手段,研究了稀土离子掺杂浓度对ZAS微晶玻璃的结构和发光性能的影响。XRD结果表明,ZAS[DK]:RE3+ (RE=Eu,Tb,Ce)微晶玻璃包含ZnAl2O4晶相和SiO2非晶相,ZnAl2O4平均晶粒尺寸约为30 nm,稀土离子的掺杂没有显著改变原来的ZnAl2O4晶体结构。TEM结果表明,900 ℃时ZnAl2O4从ZAS体系中析出。PL光谱显示,Eu3+ 存在 5D0→7F2跃迁,ZAS[DK]:Eu3+在611 nm 处发出强烈的红色光;由于Tb3+ 的5D4→7F5 跃迁,ZAS[DK]:Tb3+在541 nm 处发出明亮的绿色光;ZAS[DK]:Ce3+ 在381 nm处显示了蓝光发射,对应于Ce3+ 的5d→4f 轨道跃迁。ZAS[DK]:RE3+ (RE=Eu, Tb, Ce)的PL发射光谱存在着浓度猝灭现象,Eu3+、Tb3+ 和Ce3+的最佳单掺杂摩尔分数分别为20%、20%和3%。CIE色度图表明,ZAS[DK]: RE3+ (RE=Eu,Tb,Ce)的色坐标分别位于红光、绿光和蓝光区域。实验结果表明,ZAS:RE3+ (RE=Eu,Tb,Ce) 微晶玻璃是一种良好的可用于全色显示的白光LED材料。 相似文献
54.
以哌嗪为模板剂,在水-乙醇混合溶剂体系中溶剂热合成了两个具有三维开放骨架结构的稀土硫酸盐[Ln4(H2O)4(SO4)10](C4N2H12)4(H2O)4(Ln = Gd,化合物1和Eu,化合物2),并对其进行了结构表征、热重以及荧光光谱分析. 单晶结构解析表明,化合物1和2属于同构异质,均结晶于单斜晶系,P21/c空间群,化合物1,a = 19.691(3) ?,b = 19.249(3) ?,c = 13.186(2) ?,β = 92.33(0)o,V = 4993.5(1) ?3, Z =4. 化合物2,a = 19.7233(8) ?,b = 19.2791(8) ?,c = 13.2095(5) ?,β = 92.329(1)o,V = 5018.7(3) ?3, Z =4. 两个化合物在ab平面上由SO4,GdO8和GdO9多面体共边或共角交错连接形成含有八元环和十六元环的二维层状结构,该二维层沿c方向平行排列,相邻层通过SO4四面体相连形成具有孔道的三维开放骨架结构,其孔道之中包含平衡骨架负电荷的质子化哌嗪分子. 化合物2的固体荧光光谱分析显示其在397nm激发波长下,表现出典型的Eu3+发光性质. 相似文献
55.
Six new ternary rare-earth (La, Eu, Sm, Nd, Y, Yb) complexes with L-isoleucine and 1,10-phenanthroline have been synthesized. Their compositions were characterized as RE(Ile)3PhenCl3 · 4H2O (RE = La, Eu, Sm, Nd, Y, Yb; Ile = L-isoleucine; phen = 1,10-phenanthroline) by elemental analysis, EDTA titration, molar conductance measurement, UV spectra, FT-IR spectra, and TG-DTA. The average diameters of growth inhibition area and the minimal inhibitory concentration (MIC) of the complexes were studied by disc diffusion method and dilution method in nutrient broth. The results showed that the ternary rare-earth complexes strongly exhibited the antibacterial activity against Escherichia coli and Staphylococcus aureus and that their antibacterial effects were better than those of rare-earth chlorides, L-isoleucine, and 1,10-phenanthroline. 相似文献
56.
C. Guzmán-Afonso J. López-Solano C. González-Silgo S.F. León-Luis E. Matesanz A. Mujica 《高压研究》2013,33(2):184-190
We have studied the high pressure behavior of the α and β′-phases of Tb 2(MoO 4)3 using a combination of powder X-ray diffraction and ab initio calculations. The α-Tb 2(MoO 4)3 phase did not undergo any structural phase transition in the pressure range from 0 up to the maximum experimental pressure of 21 GPa. We observed line broadening of the diffraction patterns at pressures above 7 GPa, which may be due to non-hydrostatic conditions. The complete amorphization of the sample was not reached in the pressure range studied, as expected from previous Raman studies. The behavior under pressure of the β′-Tb 2(MoO 4)3 phase is similar to that of other rare-earths trimolybdates with the same structure at room temperature. A phase transition was observed at 2 GPa. The new phase, which can be identified as the δ-phase, has never been completely characterized by diffraction studies. A tentative indexation has been performed and good refined cell parameters were obtained. We detect indications of amorphization of the δ-Tb 2(MoO 4)3 phase at 5 GPa. 相似文献
57.
A study is made of the luminescence of rare-earth-metal (REM)-doped anode oxide films (AOF) grown on aluminu. It is shown
that REMs introduced into an AOF in the course of its formation exert a considerable influence on the position of the maximum
half-width and the intensity of the luminescence spectrum of the matrix, i.e., Al2O3. Photoelectrochemical properties of AOF (Eu) are investigated. A dependence of the AOF photopotential on the conditions of
its formation is shown.
Belarusian State University of Information Science and Radioelectronics, 6, P. Brovka St., Minsk, 220600, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 4, pp. 593–596, July–August, 1998. 相似文献
58.
B. G. Tagiev A. B. Abdullaev O. B. Tagiev G. A. Kasimova F. N. Sultanov B. M. Izzatov N. N. Musaeva R. B. Dzhabbarov A. N. Georgobiani L. S. Lepnev Z. P. Ilyukhina 《Journal of Applied Spectroscopy》1995,62(3):524-529
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 145–151, May–June, 1995. 相似文献
59.
Rare-earth doped fibers suffer from relatively high attenuation in comparison to conventional communication fibers. In order to improve the properties of such fibers, understanding of the mechanisms involved in scattering effects is of great importance. The effect of Nd-doping, Al-codoping and of the drawing temperature on the scattering effect was investigated for several different optical fibers. To this end a measuring setup was realized which allows absolute measurements of the scattering coefficient at different positions along a fiber. Also separation of total attenuation and scattering effects is possible. The presented results indicate scattering effects as primary source for increased attenuation compared with undoped fibers. 相似文献
60.
稀土金属元素的硅化物在n型硅衬底上具有高电导率和低肖特基势垒的特点,在大规模集成的微电子器件领域具有很好的应用价值.文章系统介绍了在Si(001)表面自组装生长的稀土金属硅化物纳米结构的研究进展,较全面地讨论了退火温度、退火时间以及稀土金属表面覆盖度等生长条件对纳米结构生长的影响作用,并在此基础上分析了纳米线、纳米岛的晶化结构,衬底对纳米结构生长的影响,以及纳米结构的演化过程.搞清楚这些内在的生长机理,有助于人们今后实现可严格控制稀土金属硅化物纳米结构的形貌尺寸和分布的自组装生长.此外,文章还介绍了目前人们对稀土金属硅化物纳米线电学性质的研究进展. 相似文献