Effects of rare-earth elements on the glass-forming ability and mechanical properties of Cu_(46)Zr_(47-x)Al_7M_x(M = Ce,Pr,Tb,and Gd) bulk metallic glasses

Cu46Zr47-xA17Mx （M = Ce, Pr, Tb, and Gd） bulk metallic glassy （BMG） alloys were prepared by copper-mold vacuum suction casting. The effects of rare-earth elements on the glass-forming ability （GFA）, thermal stability, and mechanical properties of Cu46Zr47-xA17Mx were investigated. The GFA of Cu46Zr47-xA17Mx （M = Ce, Pr） alloys is dependent on the content of Ce and Pr, and the optimal content is 4 at.%. Cu46Zr47-xA17Thx（X = 2, 4, and 5） amorphous alloys with a diameter of 5 mm can be prepared. The GFA of Cu46Zr47-xA17Gdx（x = 2, 4, and 5） increases with increasing Gd. Tx and Tp of all decrease. Tg is dependent on the rare-earth element and its content. ATx for most of these alloys decreases except the Cu46Zra2Al7Gd5 alloy. The activation energies △Eg, △Ex, and △Ep for the Cu46Zr42A17Gd5 BMG alloy with Kissinger equations are 340.7, 211.3, and 211.3 kJ/mol, respectively. These values with Ozawa equations are 334.8, 210.3, and 210.3 kJ/mol, respec- tively. The Cu46Zr45Al7Tb2 alloy presents the highest microhardness, Hv 590, while the Cu46Zr43A17Pr4 alloy presents the least, Hv 479. The compressive strength （at.f.） of the Cu46Zra3A17Gd4 BMG alloy is higher than that of the Cu46Zr43Al7Tb4 BMG alloy.

Design of the rare-earth-containing materials based on the micro-alloying phase equilibria, phase diagrams and phase transformations

Rare-earth(RE)elements,known as“industrial vitamins”,have permeated modern lives,especially in high-tech applications.Although the RE elements possess close chemical similarities and have been treated as“one element”in the periodic table,their characteristics differ from each other.The RE microalloying effect is the crux to ameliorate the physicomechanical and thermochemical properties of materials,thereby the study of RE-related phase diagrams becomes indispensable to the design and optimization of RE-containing materials.However,in reality,the knowledge base in this area is considerably scarce compared with that of other commonly-used elements.In this work,the phase equilibria,phase diagrams,phase transformations,and some recent examples of RE-containing materials design are summarized,with which one can predict the RE solubilities,the RE precipitates,as well as the corresponding service behaviors.The attainment of enhanced materials’properties suggests that the thermodynamic rules extracted from the phase diagrams could serve as fundamental criteria for the successful development of novel RE-containing materials.

稀土发光材料在印染加工中的应用研究

将具有余辉效应的稀土发光材料配制成添加剂,并按比例添加到染色和印花色浆中,对涤纶及苎麻织物分别进行了染色和印花实验,印染成品的得色深度和鲜艳度有明显提高;对添加剂及其在印染加工中的增深增艳机理进行了粗浅讨论。

稀土发光材料在印染加工中的应用研究

将具有余辉效应的稀土发光材料配制成添加剂，并按比例添加到染色和印花色浆中，对涤纶及苎麻织物分别进行了染色和印花实验，印染成品的得色深度和鲜艳度有明显提高；对添加剂及其在印染加工中的增深增艳机理进行了粗浅讨论。

Coordination chemistry of surface-associated ligands for solid-liquid adsorption of rare-earth elements

General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination chemistry.Relevant properties of ligands include selectivity of metal ions based on adjustment of donor atom polarizability,denticity,and the pKarange of the binding sites.The selectivity of solid-phase materials for the enrichment of rare-earth ions by the ligand design guidelines is outlined,with special consideration of additional variable factors including steric hindrance,saturated binding sites,variability in speciation caused by the identity of counterions and ionic strength,and size-exclusivity in ligands stemming from differences in bite angle,preo rganization of ligands,or intraligand interactions.This review analyzes some principles of selectivity of rare-earth elements with ligands organized by donor type from examples collected from reports published between 2009 and 2021.

Preparation of rare-earth element doped Mg_2Si by FAPAS

Rare-earth elements（Re） Sc and Y doped Mg_2Si thermoelectric materials were made via a field-activated and pressure-assisted synthesis（FAPAS） method at 1023-1073 K,50 MPa for 15 min.The samples created using this method have uniform and compact structures.The average grain size was about 1.5-2μm,the micro-content of Re did not change the matrix morphology.The sample with 2500 ppm Sc obtained the best Seebeck coefficient absolute value,about 1.93 times of that belonging to non-doped Mg_2Si at about 408 K.The electric conductivity of the sample doped with 2000 ppm Y becomes 1.69 times of that of pure Mg_2Si at 468 K,while the former had a better comprehensive electrical performance.Their thermal conductivity was reduced to 70%and 84% of that of non-doped Mg_2Si.Thus,the figure of merit and ZT of these two samples were enhanced visibly,which were 3.3 and 2.4 times of the non-doped samples at 408 K and 468 K,respectively.The maximal ZT belonging to samples doped with 2500 ppm Sc went up to 0.42 at about 498 K,higher than 0.40 of sample doped with 2000 ppm Y at 528 K and 0.25 of non-doped Mg_2Si at 678 K,and the samples doped with Sc seemed to get the best thermoelectric performances at lower temperature.

稀土铕配合物发光材料的制备与应用

稀土铕发光材料因其具有较强的特征荧光,而且具有色纯度高、化学稳定性好、激发寿命较长和理论量子效率高等优点,已成为生物、医学、光、电、磁等领域研究的重要内容。本文主要总结了由稀土铕掺杂配合物制备发光材料的研究进展,从发光性质、稀土发光材料以及稀土铕掺杂配合物等方面展开论述。着重讨论近年来稀土铕掺杂配合物在新型发光材料方面发挥的作用以及相关研究成果,并展望了稀土发光材料的应用前景。