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Abstract: A reddish orange light emissive long afterglow phosphor, Ca2SnO4:Sm3+ was prepared by sol–gel method at lower temperature. The synthesized phosphors were characterized by X-ray diffraction, scanning electron micrograph images, photoluminescence spectra, afterglow decay curves and thermoluminescence spectra. Three emission peaks locate at 565nm, 609nm and 655nm corresponding to CIE chromaticity coordinates of x =0.53 and y =0.47, which indicates the reddish orange light emitting. The fluorescent intensity and the afterglow characteristic depends on the concentration of Sm3+ and the optimized concentration is 1.5mol%. The afterglow decay curves are well fitted with triple-exponential decay models. The thermoluminescence glow curves show that the Sm3+ induces suitable trap depth and result in the long afterglow phenomenon, and the corresponding increase or decrease in afterglow is associated with trap concentration, nearly no change in trap depth. The 1.5mol% Sm3+-doped Ca2SnO4 sample has the biggest trap concentration and exhibit the best afterglow characteristic, its’ afterglow time is about 1h. The phosphorescence mechanism of this long afterglow phosphor was discussed. [Copyright &y& Elsevier]

Abstract: A novel orange emissive phosphor, Sm3+-doped SrWO4, was synthesized by high temperature solid-state reaction in air atmosphere. The excitation spectra show that the phosphors can be efficiently excited by ultraviolet and near-ultraviolet light, the optimized concentration is 4mol%. Three emission peaks locate at 562, 596 and 642nm, corresponding to CIE chromaticity coordinates of (x =0.54, y =0.46), which indicates the orange light emitting. The decay curves are well fitted with triple-exponential decay models. The quantum yield of the Sr0.96Sm0.04WO4 phosphor is about 70.65% under excitation of 377nm. Furthermore, the temperature-dependent luminescence indicates the phosphor exhibits a small thermal-quenching property. So the phosphor is able to be applied to UV-LED chip-based white light-emitting diodes. [Copyright &y& Elsevier]

A new complex with the formula [Na(H 2 O) 2 ] 6 [MoCo 6 O 12 (H 2 O) 12 ] · 4.3H 2 O has been synthesized and characterized by single crystal X‐ray diffraction, thermal study, infrared spectrum. The complex is rose rhombic crystal and space group R‐3 m with a=11.9396(15) Å, b=11.9396(15) Å, c=22.995(3) Å, α=90°, β=90°, γ=120°, V=2838.9(9) Å 3 , Z=3, and R 1 =0.0612. The structure of the anion [MoCo 6 O 12 (H 2 O) 12 ] 6- has a hexagonal plane structure composed of a central Mo ion surrounded by six octahedron CoO 6 groups. Each CoO 6 shares an edge with each of its two neighboring CoO 6 and another edge with the MoO 6 octahedron. This is similar to the Anderson‐type strucure. This new complex is colbaltmolybdate described. [ABSTRACT FROM AUTHOR]

Abstract: A novel white light emitting long lasting phosphorescent material Ca3SnSi2O9: Dy3+ was synthesized by conventional solid-state reaction method. It shows a white light emitting phosphorescence at room temperature after the 254nm UV light irradiation stopped, and it is considered that the phosphorescence originates from the mixture of Dy3+ characteristic luminescence. The thermoluminescence (TL) spectra show that Dy3+ ion induces a proper trap in the phosphor with the depth of 0.402eV and results in long afterglow phosphorescence. [Copyright &y& Elsevier]

Abstract: A facile coumarin-based Schiff base sensor, 7-hydroxy-8-((2-hydroxy-phenylimino)methyl)-coumarin (H2L), has been designed and synthesized for selective detection of Al3+ in methanol–water (1:1, v/v). A fluorescence enhancement of 12-fold at 528nm can be realized upon addition of 5.0 equiv. Al3+ with excitation at 421nm. The mechanism of C N isomerization, coupled with photoinduced energy transfer, is proposed to explain the observed spectral response. Most importantly, this Al3+ sensor has good water-solubility and can be excited with light in the visible range. [Copyright &y& Elsevier]

Objective: To study the effect on promoter de-methylation, expression of ALDH1a2 gene and cell apoptosis by treated with 5-Aza-dC and TSA in five human bladder cancer cell lines., Methods: Human bladder cancer cell lines RT-4, 253J, 5637, BIU-87 and T24 were cultured and treated with 5-Aza-dC and(or) TSA. The expression of the ALDH1a2 gene was detected by RT-PCR and Western blot. The methylation status of gene promoter was determined by MSP, and the cell cycle profile was established by flow cytometry., Results: ALDH1a2 was silenced in five human bladder cancer cell lines. Re-expression of ALDH1a2 was detected after treated with 5-Aza-dC alone or TSA in combination. ALDH1a2 transcript was marked in each cell lines combined with 5-Aza-dC and TSA treatment which showed a synergistic effect on expression of ALDH1a2 transcript. Early apoptotic was the main mode of apoptosis and death of human bladder cancer cell lines induced by 5-Aza-dC and TSA. The percentage of early apoptotic cells was 1.4% in control group and 2.8% in TSA group, however, 20.2% in 5-Aza-dC group and 33.8% in 5-Aza-dC + TSA group, respectively. The groups of TSA, 5-Aza-dC and 5-Aza-dC + TSA were significantly different from control group (P < 0.05)., Conclusions: Aberrant methylation of ALDH1a2 gene is the main cause for gene transcriptional inactivation. Re-expression of ALDH1a2 gene and cell apoptosis are detected after either treatment with 5-Aza-dC alone or in combination with TSA.

In the mol-ecule of the title compound, C(7)H(8)O(2), the phenol O and hydroxy-methyl C atoms lie in the ring plane [deviations of -0.015 (3) and and 0.013 (3) Å, respectively]. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link mol-ecules into a network. A weak C-H⋯π inter-action is also found.