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Ho3+-doped and Ho3+/Yb3+-codoped lead bismuth gallate (PBG) oxide glasses were prepared and their spectroscopic properties were investigated. The derived Judd–Ofelt intensity parameters (Ω2=6.81×10-20 cm2, Ω4=2.31×10-20 cm2, and Ω6=0.67×10-20 cm2) indicate a higher asymmetry and stronger covalent environment for Ho3+ sites in PBG glass compared with those in tellurite, fluoride (ZBLAN), and some other lead-contained glasses. Intense frequency upconversion emissions peaking at 547, 662, and 756 nm as well as infrared emissions at 1.20 and 2.05 μm in Ho3+/Yb3+-codoped PBG glass were observed, confirming that energy transfer between Yb3+ and Ho3+ takes place, and a two-phonon-assisted energy transfer from Yb3+ to Ho3+ ions was determined by the calculation using phonon sideband theory. The 1.20 μm emission observed was primarily due to the weak multiphonon deexcitation originated from the small phonon energy of PBG glass (∼535 cm-1). A large product of emission cross-section and measured lifetime (9.93×10-25 cm2 s) was obtained for the 1.20 μm emission and the gain coefficient dependence on wavelength with population inversion rate (P) was performed. The peak emission cross-section for 2.05 μm emission was calculated to be 4.75×10-21 cm2. The relative mechanism of Ho3+-doped and Ho3+/Yb3+-codoped PBG glasses on their spectroscopic properties was also discussed. Our results suggest that Ho3+/Yb3+-doped PBG glasses are a good potential candidate for the frequency upconversion devices and infrared amplifiers/lasers. [ABSTRACT FROM AUTHOR]

Transparent Tb3+ and Yb3+ codoped oxyfluoride glass ceramics containing CaF2 nanocrystals were prepared by melt quenching and subsequent heat treatment. Crystallization kinetics of CaF2 nanocrystals was investigated by differential scanning calorimetric method. The average apparent activation energy Ea of the crystallization was ∼498 kJ/mol. Moreover, the value of the Avrami exponent n was 1.01. These results suggest that the crystallization mechanism of CaF2 is a diffusion controlled growth process of needles and plates of finite long dimensions. X-ray diffraction patterns and transmission electron microscopy image confirmed the CaF2 nanocrystals in the glass ceramic. Ultraviolet (UV) and visible emission spectra of the as-made glass and the glass ceramic with an excitation of a 974 nm laser diode were recorded at room temperature. An intense UV emission at 381 nm was observed in the glass ceramic. The origin of the enhancement of the emission at 381 nm was investigated using spectroscopic technique and Judd-Ofelt analysis. The enhancement of the emission at 381 nm could be attributed to the change of the ligand field of Tb3+ ions due to the incorporation of some Tb3+ and Yb3+ ions into CaF2 nanocrystals in the glass ceramic. [ABSTRACT FROM AUTHOR]

Tb3+‐doped germanate glass ceramics containing CaF2 nanocrystals were prepared by melt quenching method with subsequent heat treatment. Their microstructures were investigated by XRD and TEM techniques. Their optical properties were studied by the transmittance, the photoluminescence, and the X‐ray excited luminescence (XEL). The luminescence intensity in the glass ceramics under 377 nm light and X‐ray excitations is significantly enhanced. The maximum integrated XEL intensity of the glass ceramics is about 50% of that of the commercial Bi4Ge3O12 (BGO) scintillating crystal. The results indicate that Tb3+‐doped germanate glass ceramic could be a promising scintillating material used in X‐ray detection for slow event. [ABSTRACT FROM AUTHOR]

Anastrozole is currently used as first‐line treatment in locally advanced or metastatic breast cancer. A generic anastrozole tablet was developed to offer an alternative to the marketed tablet formulation. The aim of the current study was to evaluate the bioequivalence between the test and reference formulations of anastrozole in a single‐dose, 2‐period, 2‐sequence crossover study with a 14‐day washout interval. A total of 20 healthy male Chinese volunteers were enrolled and completed the study, after oral administration of a single dose of 1.0‐mg test and reference formulations of anastrozole. The blood samples were collected at different times and were determined by a fully validated high‐pressure liquid chromatography–tandem mass spectrometry method. The evaluated pharmacokinetic parameters, including Cmax, AUC0–t, and AUC0–∞, were assessed for bioequivalence based on current guidelines. The observed pharmacokinetic parameters of anastrozole of the test drug were similar to those of the reference formulation. The 90% confidence intervals of test/reference ratios for Cmax, AUC0−t, and AUC0−∞ were within the bioequivalence acceptance range of 80%–125%. The results obtained from these healthy Chinese subjects in this study suggest that the test formulation of anastrozole 1.0‐mg tablet is bioequivalent to the reference formulation (Arimidex 1.0‐mg tablet). [ABSTRACT FROM AUTHOR]

Residential indoor exposure to volatile organic compounds (VOCs) is a major public health concern. However, the relevant pollution sources have not been well characterized in China. In this study, the 24-h integrated concentrations of 55 VOC species in 27 urban residences, Beijing were measured in the summer. The sources were characterized with positive matrix factorization (PMF) and general linear model (GLM). The most abundant species in terms of geometric mean concentration were formaldehyde (55.1 μg/m 3 ), acetaldehyde (18.7 μg/m 3 ), acetone (14.8 μg/m 3 ), toluene (14.1 μg/m 3 ), hexanal (13.8 μg/m 3 ), n -hexadecane (8.9 μg/m 3 ) and n -pentadecane (8.5 μg/m 3 ). PMF generated 7 factors associated with VOC sources, including aldehydes from ozone-initiated secondary reactions, butyraldehyde from hydrolysis of building materials and furniture, wood flooring emission, wooden furniture emission, wall coverings emission, mobile emission and halogenated hydrocarbons of miscellaneous outdoor origin. GLM identified leather sofa as another source of indoor terpenes and formaldehyde. GLM also found composite wood flooring had stronger emission of VOCs than solid wood flooring, except 1,4-dichlorobenzene. A comparison with multiple studies across the world suggested that: (1) more intensive ozone-initiated secondary reactions resulted in the significantly higher indoor carbonyl concentrations in Beijing than in Japan and USA in the summer; (2) the indoor concentrations of benzene and C 12 -C 17 alkanes were much higher in Beijing, due to the traffic conditions and prevalent use of wood flooring varnishing. [ABSTRACT FROM AUTHOR]

Autism Spectrum Disorder (ASD) is a developmental disorder with different levels of severity. Although the exact causes of ASD is not yet known, nor is there a medical cure for ASD to date, special facilities and schools have been established to help individuals coping better and becoming more independent. With the advancement in Virtual Reality (VR) technology, there has been a greater depth of development of technology-enhanced game-based learning for children with ASD. This paper will describe our effort on virtual pink dolphins to assist children with ASD in their learning, at the same time, to avoid the use of physical pink dolphins which is a species endangered. A study on the use of a low-cost VR enabled pink dolphins game for children with ASD to learn direction following, psychomotor skills and hand-eye coordination will be reported. [ABSTRACT FROM AUTHOR]

A portable all-fiber thermometer based on the FIR technique in Er3+/Yb3+ co-doped TeO2–WO3–La2O3–Na2O (TWLN) glasses was designed and its temperature sensing performance in the temperature range of 293–569 K was determined in detail. The high glass transition temperature (Tg = 439 °C) of TWLN glass contributes to broadening the range of temperature measurement. The spectroscopic analysis of Eu3+ ions and Judd–Ofelt analysis of Er3+ ions reveal that the rare earth ions are situated in a low symmetry environment in TWLN glass, which suggests that a large FIR change and high temperature sensitivity are expected. Intense green upconversion emission in Er3+/Yb3+ co-doped TWLN glass fiber was easily observed under 980 nm excitation at a low pumping power (1.4 mW). The maximum temperature sensitivity of the portable all-fiber thermometer reached 86.7 × 10−4 K−1 at 553 K. Experimental results showed that the absolute errors were around ±1 K within the temperature range from 285 to 563 K. [ABSTRACT FROM AUTHOR]

The effects of downflow sludge circulation on granulation and methane recovery at low load were investigated for domestic wastewater treatment in a modified anaerobic reactor. Compared with conventional upflow anaerobic reactors, enhanced granulation with shortened start-up time was achieved and stable granules were successfully cultivated only after 58 days operations. The introduction of downflow sludge circulation resulted in reverse wastewater-sludge flow and uniform sludge distribution in the reaction zone, which contributed to enhanced wastewater-sludge mass transfer and satisfactory performance with a high soluble chemical oxygen demand (SCOD) removal efficiency of 94.8% at hydraulic retention time (HRT) 6 h. Besides, enhanced liquid-to-gas mass transfer caused a lower dissolved CH 4 saturation index of 1.11 and a higher CH 4 recovery efficiency of 79.48% at HRT 6 h. High throughput sequencing revealed a distinct shift of microbial community during start-up period from Proteobacteria to Bacteroidetes and Chloroflexi in the existence of downflow sludge circulation. [ABSTRACT FROM AUTHOR]