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Detection of Fe(III) and Cu(II) in water is highly desirable because their abnormal levels can cause serious harm to human health and environmental safety. In this work, a ratiometric luminescence sensing platform based on lanthanide-based silica nanoparticles was constructed for the detection of Fe3+ and Cu2+ ions. The terbium-silica nanoparticles (named SiO2@Tb) with dual-emission signals were successfully prepared by grafting Tb3+ ions onto trimellitic anhydride (TMA) functionalized silica nanospheres. It can serve as a ratiometric fluorescent probe for the detection of Fe3+ and Cu2+ ions in water with the green emission of Tb3+ ions as a response signal and the blue emission of silica nanospheres as the reference signal. Significantly, an easy-to-differentiate color change for visual detection was also realized. SiO2@Tb shows high sensitivity even in very low concentration regions towards the sensing of Fe3+ and Cu2+ with low detection limits of 0.75 μM and 0.91 μM, respectively. Moreover, the mechanism for the luminescence quenching of SiO2@Tb was systematically investigated, and was attributed to the synergetic effect of the absorption competition quenching (ACQ) mechanism and cation exchange. This study demonstrates that SiO2@Tb can be employed as a promising fluorescent probe for the detection of Fe3+ and Cu2+ ions, and the combination of lanthanide ions with silica nanoparticles is an effective strategy to construct a ratiometric fluorescent sensing platform for the determination of analytes in environmental detection. [ABSTRACT FROM AUTHOR]

A luminescence sensor based on an europium(III)-based lanthanide–organic framework, [Eu(BCB)(DMF)]·(DMF)1.5(H2O)2 (1), was synthesized via a solvothermal method using 4,4′,4′′-benzenetricarbonyltribenzoic acid (H3BCB) as a bridging ligand. Single-crystal X-ray diffraction indicates that Eu centers are eight-coordinated with a trigonal dodecahedron and a square antiprismatic configuration, and adjacent Eu atoms are bridged by BCB organic linkers to form a 3D rod-packing structure. Photoluminescence studies show that compound 1 emits bright red luminescence and behaves as a multi-responsive luminescent sensor toward 4-nitrophenol (4-NP) and I− and Fe3+ ions in water with high sensitivity, selectivity and low detection limits. Furthermore, the possible luminescence sensing mechanisms were also investigated by PXRD analysis, UV-vis spectroscopy and X-ray photoelectron spectroscopy (XPS). The recognition mechanism for 4-NP and I− ions can be attributed to the competition absorption and that for Fe3+ ions is considered to be a multi-quenching mechanism dominated by competition absorption. This study demonstrates that the lanthanide-based MOF might be a promising candidate for the detection of 4-NP and I− and Fe3+ ions in aqueous medium. [ABSTRACT FROM AUTHOR]

Becker's Nevus (BN) is a benign hamartoma with an esthetically troublesome condition secondary to hyperpigmentation and hypertrichosis. Many treatment modalities have been utilized with variable outcomes. To evaluate the efficacy and safety of intense pulsed light (IPL) in the treatment of BN. IPL was used at filter of 590 nm, fluence of 18–22 J/cm2, double-pulse mode (pulse width of 3–10 ms, pulse delay of 20–30 ms) at 3-month intervals. Final evaluations were performed by physician global assessment and patient satisfaction. Side effects were monitored at each treatment session and follow-up visit. Twenty-four patients (9 females, 15 males) with BN (16 hypertrichotic, 8 atrichotic) completed the study. The mean number of treatment sessions was 5 ± 2.17. The improvement in atrichotic BN group (4.87 ± 0.35) was significantly greater than that observed in hypertrichotic BN group (3.63 ± 0.89) (p =.001). Hair density simultaneously decreased with treatment in hypertrichotic BN. The mean satisfaction score was 5.75 ± 2.05 and 8 ± 0.93 in hypertrichotic and atrichotic BN groups respectively (p =.002). No repigmentation was noted during the follow-up period. No permanent side effects were observed. IPL is an effective and well-tolerated treatment option for patients with hypertrichotic and atrichotic BN. [ABSTRACT FROM AUTHOR]

Undoped n-type Bi2Te3 bulks were prepared via the liquid state manipulation (LSM) with subsequent ball milling and spark plasma sintering processes. The sample with LSM obtains higher carrier concentration and larger effective mass compared with that without LSM, exhibiting favourable electrical transport properties. More importantly, a much reduced lattice thermal conductivity ~ 0.47 W m−1 K−1 (decreased by 43%) is obtained, due to the enhanced multiscale phonon scattering from hierarchical microstructures, including boundaries, nanograins and lattice dislocations. Additionally, due to the increased carrier concentration and enlarged band gap, the bipolar effect is effectively suppressed in sample BT-LSM. Consequently, zTmax ~ 0.66 is achieved in the sample with LSM at higher temperature of 475 K, almost 22% improvement compared with that of the contrast. [ABSTRACT FROM AUTHOR]

Detection of Fe(III) and Cu(II) in water is highly desirable because their abnormal levels can cause serious harm to human health and environmental safety. In this work, a ratiometric luminescence sensing platform based on lanthanide-based silica nanoparticles was constructed for the detection of Fe 3+ and Cu 2+ ions. The terbium-silica nanoparticles (named SiO 2 @Tb) with dual-emission signals were successfully prepared by grafting Tb 3+ ions onto trimellitic anhydride (TMA) functionalized silica nanospheres. It can serve as a ratiometric fluorescent probe for the detection of Fe 3+ and Cu 2+ ions in water with the green emission of Tb 3+ ions as a response signal and the blue emission of silica nanospheres as the reference signal. Significantly, an easy-to-differentiate color change for visual detection was also realized. SiO 2 @Tb shows high sensitivity even in very low concentration regions towards the sensing of Fe 3+ and Cu 2+ with low detection limits of 0.75 μM and 0.91 μM, respectively. Moreover, the mechanism for the luminescence quenching of SiO 2 @Tb was systematically investigated, and was attributed to the synergetic effect of the absorption competition quenching (ACQ) mechanism and cation exchange. This study demonstrates that SiO 2 @Tb can be employed as a promising fluorescent probe for the detection of Fe 3+ and Cu 2+ ions, and the combination of lanthanide ions with silica nanoparticles is an effective strategy to construct a ratiometric fluorescent sensing platform for the determination of analytes in environmental detection.

A luminescence sensor based on an europium(III)-based lanthanide-organic framework, [Eu(BCB)(DMF)]·(DMF) 1.5 (H 2 O) 2 (1), was synthesized via a solvothermal method using 4,4',4''-benzenetricarbonyltribenzoic acid (H 3 BCB) as a bridging ligand. Single-crystal X-ray diffraction indicates that Eu centers are eight-coordinated with a trigonal dodecahedron and a square antiprismatic configuration, and adjacent Eu atoms are bridged by BCB organic linkers to form a 3D rod-packing structure. Photoluminescence studies show that compound 1 emits bright red luminescence and behaves as a multi-responsive luminescent sensor toward 4-nitrophenol (4-NP) and I - and Fe 3+ ions in water with high sensitivity, selectivity and low detection limits. Furthermore, the possible luminescence sensing mechanisms were also investigated by PXRD analysis, UV-vis spectroscopy and X-ray photoelectron spectroscopy (XPS). The recognition mechanism for 4-NP and I - ions can be attributed to the competition absorption and that for Fe 3+ ions is considered to be a multi-quenching mechanism dominated by competition absorption. This study demonstrates that the lanthanide-based MOF might be a promising candidate for the detection of 4-NP and I - and Fe 3+ ions in aqueous medium.

To improve sustainable development, increasingly more attention has been paid to the evaluation of the resilience to waterlogging disasters. This paper proposed a projection pursuit model (PPM) improved by quantum particle swarm optimization (QPSO) for the evaluation of the resilience of subway station projects to waterlogging disasters. In view of the lack of research results related to the evaluation of the resilience of subway station projects to waterlogging disasters, 16 secondary indicators that affected the ability of subway station projects to recover from waterlogging disasters were identified from defense, recovery, and adaptability, for the first time. A PPM improved by QPSO was then proposed to effectively deal with the high-dimensional data about the resilience of subway station projects to waterlogging disasters. The QPSO was used to solve the best projection vector of the PPM, and interpolation algorithm was used to construct the mathematical model of evaluation. Finally, four station projects of Chengdu Metro Line 11 in China were selected for a case study analysis. The case study revealed that, among the secondary indicators, the emergency plan of construction order, the exercise frequency of emergency plans, and relief supplies had the greatest weights. The recovery was found to be the most important in the primary indicators. The values of the resilience of Lushan Avenue Station, Miaoeryan Station, Shenyang Road Station, and Tianfu CBD North Station to waterlogging disasters were found to be 2, 1.6571, 2.8318, and 3 respectively. This resilience ranking was consistent with the actual disaster situation in the flood season of 2019. In addition, the case study results showed that QPSO had the advantages of fewer parameter settings and a faster convergence speed as compared with PSO and the genetic algorithm.