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Rinta Sato Dr. Kosuke Suzuki Midori Sugawa Prof. Dr. Noritaka Mizuno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(39):12982-12990
Polyoxometalates (POMs) with heterodinuclear lanthanoid cores, TBA8H4[{Ln(μ2‐OH)2Ln′}(γ‐SiW10O36)2] ( LnLn′ ; Ln=Gd, Dy; Ln′=Eu, Yb, Lu; TBA=tetra‐n‐butylammonium), were successfully synthesized through the stepwise incorporation of two types of lanthanoid cations into the vacant sites of lacunary [γ‐SiW10O36]8? units without the use of templating cations. The incorporation of a Ln3+ ion into the vacant site between two [γ‐SiW10O36]8? units afforded mononuclear Ln3+‐containing sandwich‐type POMs with vacant sites ( Ln1 ; TBA8H5[{Ln(H2O)4}(γ‐SiW10O36)2]; Ln=Dy, Gd, La). The vacant sites in Ln1 were surrounded by coordinating W? O and Ln? O oxygen atoms. On the addition of one equivalent of [Ln′(acac)3] to solutions of Dy1 or Gd1 in 1,2‐dichloroethane (DCE), heterodinuclear lanthanoid cores with bis(μ2‐OH) bridging ligands, [Dy(μ2‐OH)2Ln′]4+, were selectively synthesized ( LnLn′ ; Ln=Dy, Gd; Ln′=Eu, Yb, Lu). On the other hand, La1 , which contained the largest lanthanoid cation, could not accommodate a second Ln′3+ ion. DyLn′ showed single‐molecule magnet behavior and their energy barriers for magnetization reversal (ΔE/kB) could be manipulated by adjusting the coordination geometry and anisotropy of the Dy3+ ion by tuning the adjacent Ln′3+ ion in the heterodinuclear [Dy(μ2‐OH)2Ln′]4+ cores. The energy barriers increased in the order: DyLu (ΔE/kB=48 K)< DyYb (53 K)< DyDy (66 K)< DyEu (73 K), with an increase in the ionic radii of Ln′3+; DyEu showed the highest energy barrier. 相似文献
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Customarily, speaking and singing have tended to be regarded as two completely separate sets of behaviors in clinical and educational settings. The treatment of speech and voice disorders has focused on the client's speaking ability, as this is perceived to be the main vocal behavior of concern. However, according to a broader voice-science perspective, given that the same vocal structure is used for speaking and singing, it may be possible to include singing in speech and voice therapy. In this article, a theoretical framework is proposed that indicates possible benefits from the inclusion of singing in such therapeutic settings. Based on a literature review, it is demonstrated theoretically why singing activities can potentially be exploited in the treatment of prepubertal children suffering from speech and voice disorders. Based on this theoretical framework, implications for further empirical research and practice are suggested. 相似文献
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