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By designing an orthogonal experiment with four factors and three levels, (Na0.5Bi0.495Nd0.005)TiO3 (NBT‐Nd) nanopowders were prepared using a hydrothermal method under different conditions to determine the optimum hydrothermal synthesis conditions. The synthesized NBT‐Nd nanopowders were characterized using X‐ray diffraction measurement, ultraviolet–visible spectra, photoluminescence spectra, and transmission electron microscopy to evaluate the orthogonal experimental conditions. The results showed that NBT‐Nd powders with excellent crystalline and luminescence properties could be obtained at 160°C, with a 16 h reaction time, 8 mol·L−1 NaOH, and with 0.4489 g C19H42BrN. The optimized hydrothermal method‐prepared NBT‐Nd powder has a rather pure rhombohedral perovskite structure at room temperature, and exhibits an aggregated polycrystalline structure containing nanotubes and nano‐sized particles. Under excitation of 247 nm light, strong fluorescence emissions are excited at 423 nm and 441 nm in the NBT‐Nd powder that were generated by transitions of Nd3+ from 2D5/2 to 4I9/2 and from 4G11/2 to 4I9/2, respectively. Through CIE1931 chromaticity calculation of the emission peaks, the NBT‐Nd powder was shown to emit indigo blue fluorescent light. [ABSTRACT FROM AUTHOR]

Nanoscale [(Ba 0.85 Ca 0.15) 0.995 Nd 0.005 ](Ti 0.9 Hf 0.1)O 3 (Nd-BCTH) ceramics were prepared via the hydrothermal method, and the effects of sintering temperature and holding time on the phase structure, micromorphology, electrical and optical properties of the Nd-BCTH ceramics were explored. All the Nd-BCTH ceramics present rather pure perovskite structure with composition approaching rhombohedral phase around the morphotropic phase boundary (MPB) region. The highest relative density is obtained for the sample sintered at 1220 °C for 10 h. The existence of Ba2+, Ca2+, Ti4+, Hf4+ and Nd3+ is confirmed and the elements distribute rather uniformly detected by X-ray photoelectron spectrometer (XPS) and energy dispersive X-ray (EDX) analysis. The ceramics present nanoscale grain size, which tends to increase with the increase of sintering temperature and holding time, and significantly affects dielectric constant and Curie temperature. Very thin and narrow ferroelectric hysteresis loops are observed, where a considerable energy storage density (173.88 mJ/cm3) and high energy storage efficiency (80.68%) are obtained at low electric field. The increase of sintering temperature and holding time induces a red shift at 400 nm absorption edge and a blue shift at 300 nm absorption edge in the Nd-BCTH ceramics, and all ceramics have a maximum absorption value at around 260 nm. Under the excitation of 269 nm light, the Nd-BCTH ceramics show the strongest fluorescence peak at 473 nm, corresponding to the 4G 3/2 →4I 9/2 transition, emitting indigo blue fluorescence. When the ambient temperature is above 400 °C, grains conduction dominates the conductive mechanism in the nano-sized Nd-BCTH ceramics. Such conduction can be attributed to oxygen vacancies caused due to the evaporation of alkaline-earth metals during high temperature sintering, and show typically thermally excited relaxation process. • Pure perovskite structure Nd-BCTH ceramics are prepared via the hydrothermal method. • The Nd-BCTH ceramics present a dense microstructure and all elements distribute evenly. • The dielectric constant and Curie temperature decrease, and piezoelectric properties lose due to the nanometer grain size. • The ceramics have very thin and long hysteresis loops, and present excellent low electric field energy storage performance. • Via Nd doping, the ceramics present strong fluorescent performance and realize multi-functionality. [ABSTRACT FROM AUTHOR]

By designing an orthogonal experiment with four factors and three levels, (Na 0.5 Bi 0.495 Nd 0.005 )TiO 3 (NBT-Nd) nanopowders were prepared using a hydrothermal method under different conditions to determine the optimum hydrothermal synthesis conditions. The synthesized NBT-Nd nanopowders were characterized using X-ray diffraction measurement, ultraviolet-visible spectra, photoluminescence spectra, and transmission electron microscopy to evaluate the orthogonal experimental conditions. The results showed that NBT-Nd powders with excellent crystalline and luminescence properties could be obtained at 160°C, with a 16 h reaction time, 8 mol·L -1 NaOH, and with 0.4489 g C 19 H 42 BrN. The optimized hydrothermal method-prepared NBT-Nd powder has a rather pure rhombohedral perovskite structure at room temperature, and exhibits an aggregated polycrystalline structure containing nanotubes and nano-sized particles. Under excitation of 247 nm light, strong fluorescence emissions are excited at 423 nm and 441 nm in the NBT-Nd powder that were generated by transitions of Nd 3+ from 2 D 5/2 to 4 I 9/2 and from 4 G 11/2 to 4 I 9/2 , respectively. Through CIE1931 chromaticity calculation of the emission peaks, the NBT-Nd powder was shown to emit indigo blue fluorescent light., (© 2021 John Wiley & Sons, Ltd.)

In animal models of experimental cerebral malaria (ECM), neuropathology is associated with an overwhelming inflammatory response and sequestration of leukocytes and parasite-infected RBCs in the brain. In this study, we explored the effect of vitamin D (VD; cholecalciferol) treatment on host immunity and outcome of ECM in C57BL/6 mice during Plasmodium berghei ANKA (PbA) infection. We observed that oral administration of VD both before and after PbA infection completely protected mice from ECM. VD administration significantly dampened the inducible systemic inflammatory responses with reduced circulating cytokines IFN-γ and TNF and decreased expression of these cytokines by the spleen cells. Meanwhile, VD also resulted in decreased expression of the chemokines CXCL9 and CXCL10 and cytoadhesion molecules (ICAM-1, VCAM-1, and CD36) in the brain, leading to reduced accumulation of pathogenic T cells in the brain and ultimately substantial improvement of the blood-brain barriers of PbA-infected mice. In addition, VD inhibited the differentiation, activation, and maturation of splenic dendritic cells. Meanwhile, regulatory T cells and IL-10 expression levels were upregulated upon VD treatment. These data collectively demonstrated the suppressive function of VD on host inflammatory responses, which provides significant survival benefits in the murine ECM model., (Copyright © 2014 by The American Association of Immunologists, Inc.)