Co(-Fe)-B-Si-Nb块体非晶合金

利用团簇线方法和微合金化原理研究了Co基Co(-Fe)-B-Si-Nb多组元合金体系中块体非晶合金的形成。首先,确定Co-B-Si三元体系为基础体系,利用团簇线(体现在三元体系中为二元特殊团簇与第三组元的连线)在Co-B-Si体系中确定基础合金成分;然后添加少量的Nb对基础三元成分进行合金化以提高合金的玻璃形成能力。利用铜模吸铸法制备直径为3mm的合金棒,结果表明能够形成块体非晶的合金成分为(Co8B3-Si)100-xNbx(x=4～5at%),其中,Co8B3为密堆附半八面体的阿基米德反棱柱团簇结构。并且这些非晶成分可近似地用(团簇)1(胶粘原子)1模型表达,为(Co8B3)1M1(M=(Si,Nb)),即非晶成分由一个团簇连接一个胶粘原子组成,其中胶粘原子M为Si和Nb原子的组合。最后用Fe替代部分Co可进一步提高合金的玻璃形成能力,得到的Co-Fe-B-Si-Nb五元块体非晶合金具有很好的软磁性能,其饱和磁化强度(Ms)最大可达0.98T,矫顽力(Hc)低于6A/m。     

微量元素对铜基块体金属玻璃形成能力的影响

研究微量元素的种类与添加量对Cu55Zr38Al7铜基块体金属玻璃形成能力的影响。X射线衍射仪和差示扫描量热仪的研究表明,添加2at%的Ag、Ti、Y或Nd都可以提高Cu55Zr38Al7的玻璃形成能力;6at%的Ag替代Cu,金属玻璃棒的临界直径可从2mm增加到4mm;而复合添加2at%的Ag和Y也可以明显提高Cu55Zr38Al7的玻璃形成能力。所以,替代化学性质相似的元素或者扩大合金系的原子尺寸范围可显著提高铜基块体金属玻璃的形成能力。     

钐离子掺杂硼硅酸盐玻璃的耐酸性及发光性质

用高温熔融方法熔制了Sm3 掺杂硼硅酸盐玻璃.对制得的玻璃进行耐酸性及发光特性测试.结果表明:在硅酸盐玻璃中掺加少量B2O3可以提高玻璃的化学稳定性.在402 nm紫外氙灯激发下,Sm3 掺杂硼硅酸盐玻璃在可见光范围内主要出现3个荧光峰,峰值波长为:568,601,647nm,分别对应于4G5/2→6H5/2,4G5/2→6H7/2,4G5/2→6H9/2跃迁,其中以601 nm处荧光峰最强,因此,Sm3 可以作为日光转换材料的有效激活离子.     

银纳米颗粒在钠钙硅酸盐玻璃中的应力分析

Ag K边X射线吸收精细结构谱分析显示,包裹在钠钙硅酸盐玻璃中的银纳米颗粒的Ag-Ag原子间最近邻距离大于体材料中Ag的间距,说明此时Ag晶格膨胀.晶格膨胀程度依赖于Ag纳米颗粒掺杂玻璃的制备条件.晶格膨胀表明:包裹在钠钙硅酸盐玻璃中的银纳米颗粒处于张应力状态,这主要是由于Ag纳米颗粒与钠钙硅酸盐玻璃基质热失配造成的.     

Relaxation dynamics of excited states of Tm3+ ions in TeO2-ZnO-Na2O-Y2O3 glasses

Tellurite glasses with the composition of xTm_2O_3-(6-x)Y_2O_3-3Na_2O-25ZnO-66TeO_2(where 0≤x≤6)were obtained by the melt-quenching technique.Absorption(300 K),excitation(300 K) and fluorescence spectra(300 K) as well as fluorescence decay curves of Tm~(3+)-doped title glasses are presented and discussed in details.The Judd-Ofelt analysis based on the room temperature absorption spectrum was applied for determination of fundamental fluorescence properties such as radiative transition probabilities(A_T),branching ratios(β_R),radiative lifetimes(τ_R) of the emitting levels of the Tm~(3+) ion and stimulated emission cross-sections(σ_(em)).Fluorescence spectra were recorded and analysed in the visible and near-infrared spectral range.The emission and effective cross-section were calculated for the ~3F_4→~3H_6 transition,showing that the investigated glasses are promising laser host materials,operating at 1.8 μm.The observed concentration quenching and non-exponential decay curves from the ~1 G_4 and ~3H_4 states indicate nonradiative energy transfer between Tm~(3+) ions.The analysis of non-exponential fluorescence decay curves from the ~1 G_4 and ~3H_4 levels was carried out in framework of the InokutiHirayama and Yokota-Tanimoto models and energy transfer microparameters were determined.The self-quenching model was proposed for describing relaxation of the first excited state of the Tm~(3+) ion.     

Synthesis of hybrid metal oxides with high degradation efficiency via a self-propagating process of metallic glasses

Establishing hetero-junctions are widely regarded as an efficient strategy in the area of photocatalysis. In this work, the series of hybrid CuO/ZrO₂/Y₂O₃ compounds were synthesized by self-propagating combustion of Cu₆₀Zr_40-xY_x (x = 0, 5, 10, 15) metallic glasses. The combustion process is self-sustaining and can be efficiently regulated with the ratio of Zr/Y. The synthesized products are irregularly shaped and uniformly dispersed with a particle size of approximately 100 nm–5 μm. The presence of Y₂O₃ in the hybrid oxides stabilizes the ZrO₂ phase and narrows the bandgap energy of as-synthesized powders. For the photocatalytic ability in degrading Methylene Blue (MB), it was demonstrated that the optimal addition of yttrium in the precursor is approximately 10 at% to the formation of best photocatalysts in the current work. Our findings not only provide the new approach to synthesize highly photocatalytic hybrid metal oxides, but also extend the functional applications of amorphous alloys.     

OH-对掺Er3+碲酸盐玻璃上转换发光的影响

研究了碲酸盐玻璃的拉曼光谱和红外光谱,分析了OH-对掺Er3 碲酸盐玻璃上转换发光的影响机制。实验结果表明,氧氟碲酸盐玻璃(TPF)的声子能量高于氧氯碲酸盐玻璃(TPC)的声子能量,但是Er3 掺杂TPF玻璃上转换发光强度也高于Er3 掺杂TPC玻璃。除水实验发现这种现象可归因于OH-的影响。随OH-浓度降低,Er3 的荧光寿命和上转换荧光都增加。在实验中,OH-对Er3 上转换发光的影响大于声子能量对Er3 上转换发光的影响,导致Er3 掺杂TPF玻璃上转换发光强度高于Er3 掺杂TPC玻璃的上转换发光。研究结果有助于进一步提高Er3 的发光效率。     

杂质对掺钕磷酸盐激光玻璃光谱性质的影响

综述了过渡金属杂质（Cu,Fe）和稀土杂质（Dy,Pr,Sm,Ce）对掺钕磷酸盐激光玻璃吸收损耗及Nd^3＋荧光猝灭影响的研究状况。     

As2S3-CdI2系统玻璃的微结构与热属性

运用传统的熔融淬冷技术成功地制备出了均匀的玻璃样品(1-x)As2S3-xCdI2(x=0．015，0．035，0．050)。对样品进行了X线衍射和热综合分析以及拉曼散射等测试。随着CdI2含量的添加，样品系统玻璃的热属性基本上没有变化。基于实验结果，被研究玻璃系统的微结构被认为是：离散的AsS3分子和Cd-S原子键或原子簇均匀地分散在由硫桥连接的[AsS3／2]单元组成的玻璃网络中。     

硫系玻璃光子晶体光纤研究进展

硫系玻璃与石英玻璃相比具有折射率高(2.0～3.5)、声子能量低(小于350 cm-1)、优良的中远红外透过性能、较宽的组分可调等特性.近年来,硫系玻璃光子晶体光纤作为一种新型中红外光子晶体光纤备受关注.回顾了硫系玻璃光子晶体光纤研究历程,从玻璃组成选择、光纤制备与损耗的降低、传输特性和结构设计、色散特性及应用等方面总...