5 resultados para Café - Maturação
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
The equilibrium properties and potential energy curves of the ground electronic state of CaF have been calculated using the Brueckner Doubles calculation with a triples contribution added [BD(T)] and the gradient-corrected density functional theory with three-parameter exact exchange mixing (B3LY-P) method, with 6-311 + G*,6-311 + G(2df,2pd) and 6-311 + G(3df,3pd) basis sets. All the computational PECs are fitted to analytical potential energy functions using Murrell-Sorbie, Huxley and Tang-Toennies potentials. Based on this, the spectroscopic parameters are calculated, and then compared with some other theoretical and experimental data. (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
采用提拉法生长了质量优异的Yb:Ca5(PO4)2F(Yb:FAP)晶体。运用化学腐蚀,光学显微镜、扫描电子显微镜以及能量散射光谱仪观察了该晶体中的生长条纹和包裹物等宏观缺陷,以及晶体的位错腐蚀形貌、位错密度及其分布情况,同时观察了晶体中亚晶界的形态。由晶体中位错的径向变化以及生长条纹可知:晶体在生长过程中为微凸界面生长。高温下CaF2的挥发造成了在晶体生长后期熔体中组分偏离化学计量比,出现组分过冷,形成包裹物。且位错密度显著增加。Yb:FAP晶体的各向异性使得晶体在(10 10)面的位错蚀坑形状、大小以
Resumo:
利用激光二极管(LD)抽运新型Na.Yb共掺CaF2(Na.Yb:CaF2)晶体,获得了1.05μm的自调Q激光输出。利用透射率1%的耦合输出镜,得到最低激光输出的抽运阈值功率仅为70mW。在透射率为2%的输出镜条件下,得到最大输出激光功率为390mw,此时激光的斜度效率达到20%。实验详细记录了自调Q脉冲的周期和宽度随抽运功率的变化关系,随着抽运功率的增加,自调Q脉冲的周期和宽度呈指数衰减。同时,还采用单棱镜进行光谱调谐实验,获得了1036~1059nm的自调Q激光调谐输出。
Resumo:
采用中频感应提拉法生长了Yb:FAP晶体。对晶体生长中影响晶体质量的因素特别是原料的处理、CaF2的挥发等进行了研究和讨论。运用ICP-AES测定Yb^3+离子在Yb:FAP晶体中的分凝系数。对Yb:FAP晶体进行了高分辨X射线的四圆衍射实验,结果表明晶体具有比较高的晶格完整性。