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As a widely distributed plant in Northeast China, Carex meyeriana Kunth (CMK) is generally considered to have antibacterial properties; however, there is a lack of scientific evidence for this. Therefore, we investigated the chemical composition of CMK extract and its effect against C. albicans. A total of 105 compounds were identified in the alcohol extracts of CMK by UPLC-Q-TOF-MS. Most were flavonoids, with Luteolin being the most represented. Among them, 19 compounds are found in the C. albicans lysates. After treatment with CMK ethanol extract, a significant reduction in the number of C. albicans colonies was observed in a vaginal douche solution from day 5 (p < 0.05). Furthermore, the CMK extract can reduce the number of C. albicans spores. The levels of IL-4, IL-6, IL-10, IL-1β, and TNF-α in vaginal tissues all exhibited a significant decrease (p < 0.05) compared to those in the model group as determined by ELISA. The results of HE staining showed that CMK extract can eliminate vaginal mucosa inflammation. CMK adjusts the vaginal mucosa cells by targeting twenty-six different metabolites and five specific metabolic pathways in order to effectively eliminate inflammation. Simultaneously, the CMK regulates twenty-three types of metabolites and six metabolic pathways against C. albicans infection. So, CMK strongly inhibits the growth of C. albicans and significantly reduces vaginal inflammation, making it a promising candidate for treating C. albicans infection. [ABSTRACT FROM AUTHOR]

Systematic crystallization of KLn(MoO4)2 double molybdate micro/nanocrystals was achieved in this work for the family of lanthanide elements (excluding Pm) and Y via hydrothermal reaction under the optimized conditions of pH = 7, Mo/Ln molar ratio R = 5 and 200 °C, with which the intrinsic influence of lanthanide contraction on phase preference, crystallite morphology (size/shape) and crystal structure was clearly revealed. Extended synthesis also produced KLa1−xEux(MoO4)2 (KLM:xEu) and KY1−yEuy(MoO4)2 (KYM:yEu) red phosphors, and detailed spectral analysis found that the layered structure of orthorhombic KYM allows Eu3+ to have a high quenching content of ∼70 at% (y = 0.7) and higher quantum efficiency and thermal stability of luminescence. Application also indicated that the KYM:0.7Eu optimal phosphor has the potential for optical temperature sensing with the thermally coupled 5D0 and 5D1 energy levels of Eu3+. [ABSTRACT FROM AUTHOR]

Solid-state reaction at 1000 °C produces a series of Li-stuffed Li5+2x(La1−yEuy)3(Ta1−xZrx)2O12 garnet phosphors (x = 0–1, y = 0.05–0.6) that exhibit favorable efficiency and thermal stability for red luminescence under either blue or n-UV light excitation, where the optimal composition was identified to be x = 0.5 and y = 0.4. The concentration quenching of luminescence was determined to occur via electric dipole–dipole interactions. Zr4+ substitution for Ta5+, accompanied by additional Li+ for charge compensation, was found via Rietveld structure refinement and Raman/UV-Vis spectroscopy to profoundly affect the tetrahedral and octahedral occupancies of Li, the symmetry of (La/Eu)O8 dodecahedron, and the bandgap of the host lattice and cation disorder, with which the systematically varying excitation and emission behaviors of Eu3+ were deciphered. The Li6(La0.6Eu0.4)3(Ta0.5Zr0.5)2O12 optimal phosphor showed quantum yields of ∼40 and 48% under 393 and 463 nm excitations, respectively, a fluorescence lifetime of ∼0.66 ms for its main emission at 610 nm, color coordinates of around (0.653, 0.347), and can retain as high as ∼85% of its room-temperature emission intensity at 423 K. The phosphor also exhibited a favorable performance for n-UV excited LED lighting. [ABSTRACT FROM AUTHOR]

Garnet‐type Li6Ca(La0.97Yb0.02RE0.01)2Nb2O12 (RE = Ho, Er, Tm) new phosphors were successfully synthesized via solid reaction at 900°C for 5 hours, whose course of phase evolution, macroscopic/local crystal structure and up‐/down‐conversion (UC/DC) photoluminescence were clarified. Mechanistic study and materials characterization were attained via XRD, Rietveld refinement, DTA/TG, electron microscopy (FE‐SEM/TEM), and Raman/reflectance/fluorescence spectroscopies. The phosphors were shown to exhibit UC luminescence dominated by a ~ 553 nm green band (5F4/5S2 → 5I8 transition) for Ho3+, a ~ 568 nm green band (4S3/2 → 4I15/2 transition) for Er3+ and a ~ 806 nm near‐infrared band (3H4 → 3H6 transition) for Tm3+ under 978 nm laser excitation, with CIE chromaticity coordinates of around (0.31, 0.68), (0.38, 0.60) and (0.17, 0.24), respectively. Analysis of the pump‐power dependence of UC intensity indicated that all the emissions involve a two‐photon mechanism except for the ~ 486 nm blue emission of Tm3+ (1G4 → 3H6), which requires a three‐photon process. The DC luminescence of these phosphors is featured by dominant bands at ~ 553 nm for Ho3+ (green, 5F4/5S2 → 5I8 transition), ~568 nm for Er3+ (green, 4S3/2 → 4I15/2 transition) and ~ 464 nm for Tm3+ (blue, 1D2 → 3F4 transition). The UC and DC properties were also comparatively discussed. [ABSTRACT FROM AUTHOR]