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In this paper, a tetragonal LiY(MoO4)2 single crystal with a bulk size of 23 × 20 × 18 mm3 was successfully grown for the first time by a top-seeded solution growth (TSSG) method. The full-width at half maximum of the (100) and (001) crystal wafers reached 27 and 43 arcsec, respectively. The transmission spectra show that the LiY(MoO4)2 crystal possesses a wide transparency window in the range of 0.344 to 5.493 μm. The thermal property studies indicate that the LiY(MoO4)2 crystal has a relatively large specific heat of 0.735 J/(g K). The thermal conductivity coefficients were determined to be 0.935 W m−1 K−1 and 1.047 W m−1 K−1 along the a and c axes at 30 °C, respectively. It is worth noting that the crystal exhibits a comparatively small thermal expansion anisotropy of 1.35, which indicates a relatively large laser damage threshold. [ABSTRACT FROM AUTHOR]

A phosphate piezoelectric crystal Te2O(PO4)2 (TPO) was grown by the Czochralski method. The dielectric, piezoelectric, and elastic constants of the crystal were measured. The TPO crystal features a large longitudinal piezoelectric constant of d33 = 6.6 pC N−1, much better than that of GaPO4 and AlPO4. The structure–property relationships are discussed in detail. First-principles calculations and structural analysis revealed that the introduction of distorted [TeO5] groups into phosphates is beneficial for enhancing the piezoelectric properties of phosphate crystals. Furthermore, the temperature dependence of the resistivity and piezoelectric constant was also measured. The results suggest that TPO is a potential candidate for piezoelectric applications due to its large piezoelectric coefficient, good piezoelectric temperature stability, and ease in crystal growth. [ABSTRACT FROM AUTHOR]

MicroRNA-151b (miR-151b) showed altered expression in ovariectomized rat model of osteoporosis. This study established an ovariectomy-induced osteoporotic rat model to investigate the role of miR-151b in osteoblasts. Eighteen female Sprague-Dawley (SD) rats were divided randomly into Sham and OVX group (n = 9). The transfections with different miRNAs and expression vectors were confirmed by RT-qPCR. The protein expression of Msx2 was detected by Western blots. The interaction between miR-151b and Msx2D was evaluated by RNA pull-down and dual luciferase reporter assay. The expression of miR-151b was significantly increased in femoral tissues of ovariectomy-induced osteoporotic rats. The expression of osteogenesis marker genes including RUNX2, ALP, OCN, OSX, and Msx2 were all significantly increased in osteogenic medium (OM) incubated primary osteoblasts and MC3T3-E1 cells. The interaction between miR-151b and Msx2 was confirmed by luciferase reporter assay and RNA pull-down. Moreover, overexpression of miR-151b significantly inhibited Msx2 in both MC3T3-E1 cells and primary osteoblasts, while miR-151b inhibitor had the opposite effect on the expression of Msx2. In addition, in primary osteoblasts and MC3T3-E1 cells, miR-151b overexpression, or Msx2 silence significantly decreased the expression of OSX, ALP, RUNX2, and OCN. MiR-151b could inhibit osteoblast proliferation, differentiation, and mineralization via downregulating Msx2 in both MC3T3-E1 cells and primary osteoblasts. MiR-151b might serve as a novel therapeutic target for osteoporosis. miR-151b: microRNA-151b; miRNAs: microRNAs; Msx2: Msh homeobox 2; MAPK: mitogen-activated protein kinase; STAT: signal transducer and activator of transcription; SD: Sprague-Dawley; BMD: bone mineral density; qRT-PCR: quantitative reverse transcription PCR; MTT: methyl thiazolyl tetrazolium; OVX: ovariectomy; ALP: alkaline phosphatase [ABSTRACT FROM AUTHOR]

Oxide crystals have been widely used in nonlinear optics (NLO) in the ultraviolet–visible and near‐infrared regions. Most traditional oxide crystals are restricted to the mid‐infrared region due to their narrow transmission window. Hence, attempting to extend infrared cutoff wavelength of oxides has attracted much attention. Herein, we report two new tellurates Li2TiTeO6 (LTT) and Li2SnTeO6 (LST) with broad transparent regions of 0.38–6.72 and 0.38–6.86 μm, respectively, as excellent candidates for mid‐infrared NLO applications. Both LTT and LST crystallize in the orthorhombic space group Pnn2. The LTT crystal exhibits intense powder second‐order generation efficiency (26×KDP) under the fundamental wavelength of 1064 nm. First‐principles calculations and dipole moments were used to illustrate the results of the powder second‐harmonic generations based on the crystal structures. Our results provide a novel oxide NLO crystal with a strong SHG and wide transparency range. They also pave a way for the design of new oxide mid‐IR NLO crystals. [ABSTRACT FROM AUTHOR]

Li2ZrTeO6 crystals have been proved as a novel nonlinear optical material with a high laser-damage threshold (>1.3 GW cm−2) and wide transparency window. However, investigations of the anisotropic properties of Li2ZrTeO6 are impeded by the difficulty of high-quality crystal growth. Here, centimeter-sized and high-quality Li2ZrTeO6 crystals were grown by a modified top-seed solution growth method. The full-widths at half-maximum of (1¯20) and (001) wafers are 33 and 36 arcsec, respectively. Based on a large high-quality crystal, the thermal properties including thermal expansion, specific heat and thermal conductivity were studied in detail. Our results show that the Li2ZrTeO6 crystal exhibits a moderate anisotropic thermal expansion (αa/αc ≈ 5) from 25 to 500 °C. The specific heat is measured to be 0.77 to 0.902 J g−1 K−1 from 25 to 500 °C. The thermal conductivities along the a and c axes are determined to be 4.14 and 4.86 W m−1 K−1, respectively, which are superior to that of molybdenum-tellurite and tungsten-tellurite crystals. The excellent thermal properties are one of the origins of the high laser-damage threshold. In addition, the relationship between the structure and the anisotropic thermal properties is also discussed. The results indicate that the Li2ZrTeO6 crystal is a promising candidate for high-energy laser applications. [ABSTRACT FROM AUTHOR]

In this letter, a novel acousto-optical (AO) Q-switch is designed by using α-BaTeMo2O9 crystal grown by the flux method. The acousto-optical modulator (AOM) exhibits a high polarization extinction ratio of 65 dB with a rise time of 32.8 ns and insertion loss of 3.66 dB. An actively Q-switched ytterbium doped all fiber laser at 1035 nm is successfully realized by using the prepared AOM. Under a pump power of 404.9 mW, a maximum output power of 1.66 W is obtained with pulse width of 167 ns at the modulation rate of 10 kHz. The results show that the α-BaTeMo2O9 AOM is a potential Q-switch for all fiber lasers. [ABSTRACT FROM AUTHOR]

Large-sized crystals of LiNa5Mo9O30 with seeds in the a-, b- and c-directions were grown successfully by the top-seeded solution growth method. The relative dielectric constants were determined to be ε11/ε0 = 16.11, ε22/ε0 = 10.52, and ε33/ε0 = 16.78, respectively. A complete set of elastic and piezoelectric constants of the LiNa5Mo9O30 single crystal was determined by means of a resonance technique and impedance analysis at room temperature. The results show that the LiNa5Mo9O30 crystal possesses five piezoelectric constants (d15 = 0.14 pC N−1, d24 = 2.32 pC N−1, d31 = 0.17 pC N−1, d32 = 0.20 pC N−1, d33 = 1.20 pC N−1). As a polar crystal, the octahedral distortion and dipole moment of MoO6 in LiNa5Mo9O30 are analyzed and calculated to explain the relationship between the piezoelectric properties and the structure. [ABSTRACT FROM AUTHOR]

Large-sized crystals of LiNa5Mo9O30 with seeds in the a-, b- and c-directions were grown successfully by the top-seeded solution growth method. The relative dielectric constants were determined to be ε11/ε0 = 16.11, ε22/ε0 = 10.52, and ε33/ε0 = 16.78, respectively. A complete set of elastic and piezoelectric constants of the LiNa5Mo9O30 single crystal was determined by means of a resonance technique and impedance analysis at room temperature. The results show that the LiNa5Mo9O30 crystal possesses five piezoelectric constants (d15 = 0.14 pC N−1, d24 = 2.32 pC N−1, d31 = 0.17 pC N−1, d32 = 0.20 pC N−1, d33 = 1.20 pC N−1). As a polar crystal, the octahedral distortion and dipole moment of MoO6 in LiNa5Mo9O30 are analyzed and calculated to explain the relationship between the piezoelectric properties and the structure. [ABSTRACT FROM AUTHOR]

A single crystal of LiNa5Mo9O30 of 52 × 44 × 8 mm3 was successfully grown using the top-seed solution growth method. The full width at half maximum of the high-resolution X-ray diffraction rocking curve for the (100) plane is 17′′. The LiNa5Mo9O30 single crystal can transmit well from 0.31–5.35 μm. It was easily processed with a moderate hardness of 5.2. The specific heat curve increases slowly without an inflection point. The thermal expansion coefficients were measured to be αc > αa > αb, and the structure–property relationship was discussed in detail. It exhibits good thermal conductivity with κ a = 2.67 W m−1 K−1, κ b = 3.61 W m−1 K−1, and κ c = 3.22 W m−1 K−1, respectively. As a molybdenum crystal, the spontaneous Raman spectra along the a-axis with different Raman configurations were characterized. There is a strong Raman shift at 946.6 cm−1, which can be used for Raman laser applications. Our results show that the LiNa5Mo9O30 single crystal is not only a second order nonlinear optical crystal but also an excellent candidate for stimulated Raman scattering. [ABSTRACT FROM AUTHOR]

ABSTRACT Two phenoxo-bridged dinuclear copper(II) complexes (Cu2L12, Cu2L22) with N-salicylidene glycine Schiff bases were prepared and evaluated their performance for catalyzing the hydrolysis of p-nitrophenyl picolinate (PNPP). The observations reveal that the as-prepared dinuclear copper(II) complexes exhibited better activity by two to three orders of magnitude rate enhancement in comparison with the autohydrolysis rate of PNPP. Chloro-containing Cu2L22 aroused approximately three times kinetic advantage over chloro-free Cu2L12 at pH 7.0, which is probably contributed to the electron-withdrawing inductive effect of the 5′-chloride group. Moreover, it was found that the pH-responded kinetic behavior displayed an enzyme-like property for the PNPP hydrolysis by the two complexes. [ABSTRACT FROM AUTHOR]

Two novel phenoxo-bridged homobinuclear copper(II) complexes with L-threonine Schiff bases as artificial hydrolases were prepared and screened for catalytic activity in the hydrolysis ofp-nitrophenyl picolinate (PNPP), a classic model of carboxylic acid esters. Kinetic analysis testified that the two complexes exhibited good activity with rate acceleration of two orders of magnitude in aqueous solution. In addition, the one copper(II) complex containing 5’-bromo substituent was much more efficient than its bromo-free analogue, showing approximately 1.1∼5.3 times kinetic advantage over a pH range of 7.00–8.20. [Supplementary materials are available for this article. Go to the publisher's online edition ofSynthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistryfor Figures 1S–3S.] [ABSTRACT FROM PUBLISHER]