Nonlinear optical (NLO) materials are of great importance in laser science and technology, as they can expand the wavelength range provided by common laser sources. Few NLO materials, except KBe 2 BO 3 F 2 (KBBF), can practically generate deep-ultraviolet coherent light by direct second-harmonic generation process, limited by the fundamental requirements on the structure-directing optical properties. However, KBBF suffers a strong layering tendency and high toxicity of the containing beryllium, which hinder the commercial availability of KBBF. Here we report a new beryllium-free borate, Li 4 Sr(BO 3 ) 2 , which preserves the structural merits of KBBF, resulting in the desirable optical properties. Furthermore, Li 4 Sr(BO 3 ) 2 mitigates the layering tendency greatly and enhances the efficiency of second-harmonic generation by more than half that of KBBF. These results suggest that Li 4 Sr(BO 3 ) 2 is an attractive candidate for the next generation of deep-ultraviolet NLO materials. This beryllium-free borate represents a new research direction in the development of deep-ultraviolet NLO materials.

A metal-organic framework, with chiral 4(1) In(OH)(CO(2))(2) helix chains, exhibits a high CO(2) uptake under ambient conditions and outstanding selective separations of CO(2) from CH(4) or N(2). Its high stability toward humidity or even boiling water is confirmed by PXRD method.

Exceptional nonlinear optical (NLO) switching behavior, including an extremely large contrast (on/off) of ∼35 and high NLO coefficients, is displayed by a solid-state reversible quadratic NLO switch. The favorable results, induced by very fast molecular motion and anionic ordering, provides impetus for the design of a novel second-harmonic-generation switch involving molecular motion.

Glial fibrillary acidic protein (GFAP) is one of the best markers for the activation of astrocytes (AS) following injury or stress in the central nervous system (CNS). The purpose of this study was to examine the expression of GFAP and 14-3-3ε in rat AS subjected to hypoxia. We established primary cultures of AS from cerebral cortex of neonatal Sprague-Dawley rats as a model of glucose deficiency and hypoxia/ischemia-reperfusion. We analyzed the activated astrocyte markers GFAP and 14-3-3ε by western blot analysis and found that both increased over time, starting at 4 h and reaching the highest level at 72 h, at the end of the experiment. GFAP and 14-3-3ε protein localization by double-labeling immunofluorescence showed elevated expression and co-localization in the cytoplasm of AS. GFAP and 14-3-3ε expression remained elevated in AS 72 h after stress conditions, which is possibly related to the excessive activation and dysfunction of the CNS in chronic injuries.

Two classical metal clusters, Cu I 4 I 4 and Cu I 6 S 6 , are introduced as functional connecting nodes to construct a novel multi-metal-cluster MOF [(Cu I 4 1) that incorporate their inherent luminescent properties, induced by their respective metal-metal interactions. These two distinct clusters are combined together for the first time to perform as functional luminophores that display unusual dual emission with both thermochromic luminescence and near-infrared (NIR) character.

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A new noncentrosymmetric borate CsZn2B3O7 was synthesized by the solid-state reaction techniques. The crystals were obtained by flux method and are of block shape without layering tendency. Single-crystal X-ray diffraction analysis reveals that the crystal structure is composed of [Zn2BO5]∞ two-dimensional layers that are bridged by [B3O6](3-) groups to form a three-dimensional framework with one-dimensional channels occupied by Cs(+) cations along the a and c axes. Thermal analysis indicates that CsZn2B3O7 melts incongruently. UV-visible-near-IR diffuse reflectance spectrum gives a short absorption edge at 218 nm. CsZn2B3O7 is phase-matchable, with a powder second-harmonic generation (SHG) efficiency of 1.5 × KDP (KDP, potassium dihydrogen phosphate) at 1064 nm, based on the Kurtz-Perry method. These results show that CsZn2B3O7 may have prospects as a UV nonlinear optical material. Interestingly, the SHG efficiency of CsZn2B3O7 is about twice that of γ-KBe2B3O7, a structurally analogous alkaline and alkaline earth borate. First-principles calculations combined with atom-cutting analysis reveal that the ZnO4 tetrhedral groups in CsZn2B3O7 account for the SHG enhancement.