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Due to the low density, low thermal conductivity and low water absorption, porous glass-ceramics have demonstrated excellent performance for thermal insulation. Closed pore structure can greatly reduce the thermal conductivity and convection as well as achieve high mechanical strength. However, yet it is difficult to realize closed pore structure due to the critical preparation condition. Here we use Fe 2 O 3 , which is the by-product of copper tailings, to optimize the pores structures of the porous glass-ceramics and facilitate the formation of uniform closed pore structure. The porous glass-ceramics were prepared by melting-quenching method, followed by sufficiently foaming through powder sintering route with SiC powders as foaming agent. The foaming process, micro structure, pore structure and thermal insulation performance were directly observed by heating microscope, scanning electron microscope (SEM), X-ray computed tomography and infrared thermal imager. The results show that the addition of Fe 2 O 3 modified the depolymerization degree of the glass network and increased the numbers of non-bridged oxygen, decreasing the foaming temperature. The resultant closed pore structure showed a better thermal insulating performance than open pore structure. Accordingly, we achieved a low thermal conductivity of 0.19 W·m−1·K−1 with the highest specific strength of 19.55 MPa·g−1·cm−3 based on closed pore structure. [ABSTRACT FROM AUTHOR]

[Display omitted] Lung cancer is the primary cause of cancer-related mortality worldwide. The anticancer effect of stilbene has been noted in various tumor types. GMQ3, which has a stilbene-mimicking skeleton, is a novel small-molecule compound with promising antitumor activity. Our results revealed that GMQ3 not only suppressed cell proliferation and cell migration of lung cancer cells but also led to G1 phase cell cycle arrest and triggered caspase-dependent apoptosis. Furthermore, investigation of the molecular mechanism showed that GMQ3 could inhibited proliferation and induced apoptosis via the p38-MAPK/SIRT1 pathway both in vitro and in vivo. Xenograft tumor mouse models showed that GMQ3 significantly inhibited tumor growth in vivo without affecting body weight. Our findings indicated that GMQ3 exerts a strong anticancer action by suppressing cell proliferation, inhibiting cell migration and inducing cell apoptosis. Moreover, the efficacy of GMQ3 was enhanced in the presence of CDK4/6 inhibitor Abemaciclib. We conclude that GMQ3 is a promising agent with potential for lung cancer. [ABSTRACT FROM AUTHOR]

High-performance and low-cost metal halide perovskite scintillator materials have important applications in X-ray detection and imaging. However, large-sized perovskite scintillator panel with high transmittance, low toxicity and long-term stability is still lacking. Herein, Eu2+ doped cesium alkaline earth chloride nanocrystals (Eu2+: CsCaCl 3 , Eu2+: CsSrCl 3 , and Eu2+: Cs 2 BaCl 4 NCs) embedded in glasses through conventional melt-quenching and subsequent heat-treatment were developed. These NCs doped glasses exhibited highly efficient and narrowband photoluminescence in blue region. Benefitting from the large X-ray absorption coefficient and high photoluminescence quantum yied, these Eu2+: CsCaCl 3 NCs doped glass scintillator shows light yield of ∼9300 photons/MeV, detection limit of ∼213.8 μGy/s, and spatial resolution of 30.0 lp/mm. These results demonstrated that glasses containing Eu2+ doped cesium alkaline earth chloride nanocrystals are promising for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

Extensive efforts have been devoted to magneto-optical (MO) glass, owing to its remarkable potential in modern optics, encompassing diverse applications such as optical isolation, modulation, and sensing. Although the Tb ions doped glass has good MO properties, high concentrations of Tb ions tend to cluster, resulting in glass crystallization. To further improve the performance of MO glass, we must improve the solubility of Tb ions and inhibit the oxidation of paramagnetic Tb3+ to diamagnetic Tb4+ by adjusting the glass composition. In this work, we conducted a comparative study on GeO 2 -B 2 O 3 -X 2 O 3 glasses doped with Tb 2 O 3 (TGBX, where X represents Ga or La) to elucidate the effects of Ga 2 O 3 and La 2 O 3 on glass properties. Our findings reveal that TGBG glasses exhibit superior MO performance compared to TGBL glasses. Notably, the Verdet constant of TGBG glass with 45 mol.% Tb 2 O 3 at 650 nm reaches 105 rad/(T·m). Although TGBL glass exhibits a lower Verdet constant, its higher glass network connectivity and higher concentration of Tb3+ ions suggest its potential for preparing larger-sized glasses with an increased Tb3+ molar ratio. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials have wide applications in sensors, batteries, electromagnetic shielding, and mechanical reinforcement. Here, carbon nanofiber (CNF)-reinforced Ge 25 Sb 10 S 65 chalcogenide glassy composites with excellent mechanical and electrical properties were obtained. These glassy composites maintained the amorphous properties of glass. Thermodynamic parameters, microscopic morphology, and structural characteristics were further studied. Benefiting from the remarkable high strength and conductivity of CNFs, as well as the great interface connection between CNFs and glass, the electrical and mechanical properties of glassy composites were greatly enhanced. The Vickers hardness improved by 36% (from 200 kg/mm2 to 272 kg/mm2), the tensile modulus increased from 45.9 GPa to 57 GPa, and the shear modulus increased from 22.2 GPa to 23.7 GPa when the CNF concentration increased from 0 wt% to 3.0 wt%. Furthermore, DC conductivity was raised by several orders of magnitude compared with bulk glass at 293 K (from 4.55 × 10−10 S/cm to 3.15 × 10−4 S/cm) owing to the formation of a continuous conductive network. Thus, these CNF-reinforced glassy composites provide a new way for realizing multifunctional composites. [ABSTRACT FROM AUTHOR]

The nucleation and crystallization of glass-ceramics are typically influenced by early phase separation, which can impact glass properties. However, it has been challenging to characterize the nanoscale phase separation and understand the nucleation mechanism of lithium disilicate (L 2 S) glass-ceramics, which has resulted in some controversy. Here, we raised the direct evidence of nanoscale clustering in the glassy phase prior to formal nucleation and crystallization by element distribution. Firstly, the amorphous Li 3 PO 4 phase formed on the boundary between the phase separation area and residual glass matrix, and then nucleation tended to start on this phase boundary. Furthermore, the effect of phase-separation on nucleation and final crystallize products was illustrated. By sufficient phase-separation, the formation of desired Li 2 Si 2 O 5 and LiAlSi 4 O 10 microcrystals was effectively motivated, which is prerequisite for high mechanical properties and transparency. We hope this work provides guidance to rationally understand the early phase separation in glass for subsequent controlling crystallization. [ABSTRACT FROM AUTHOR]

Ho 3+ /Y 3+ co-doped BaF 2 nanocrystals were precipitated in oxyfluoride glasses through conventional melt-quenching and subsequent thermal treatment. X-ray diffraction patterns, transmission electron microscope images and absorption spectra confirmed the incorporation of Ho 3+ /Y 3+ ions into BaF 2 nanocrystals in glass-ceramics. With the gradual substitution of Ho 3+ ions by Y 3+ ions, concentration dependent energy transfer between excited Ho 3+ ions were suppressed and relative emission intensity at 1.2 μm band was enhanced. The maximum emission cross-section calculated was 0.60 × 10 −20 cm 2 in BH1-GC specimen, indicating that Ho 3+ /Y 3+ co-doped glass-ceramics have a great potential for the development of 1.2 μm band gain medium. [ABSTRACT FROM AUTHOR]

Abstract: In order to increase the quantum efficiency of solar cells by down-conversion, Pr3+ doped semiconductor ZnO quantum dots (QDs) were successfully synthesized by sol–gel method. The X-ray diffraction (XRD) results indicate that ZnO QDs have hexagonal wurtzite structure and a part of the Pr3+ ions is incorporated into the ZnO lattice. ZnO QDs have a spherical shape and diameter around 5nm, which was confirmed by the high-resolution transmission electron microscopy (HRTEM). The room-temperature photoluminescence (PL) measurements revealed both UV and visible emission from the ZnO QDs. The emission peaks of aged ZnO QDs show red shift due to a size increase of the QDs, i.e, the decrease of the band gap energy and modification of the defect states. The enhancement of the PL emission peaks at 578, 630, and 752nm was assigned to energy transfer between Pr3+ ions and ZnO QDs host. The absorption peaks at 445, 470, 485, and 590nm were observed only in Pr3+ ion doped ZnO QDs which confirms that the energy transfers from Pr3+ ions to ZnO QDs. [Copyright &y& Elsevier]