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Lanthanide‐doped up‐conversion (UC) materials with color tunable property show promising application in many fields, such as biological imaging, optical multiplexing, and information security. Although great efforts have been devoted to regulate UC emission color via modifying chemical composition, crystal structure, or external stimuli condition, it is remain a daunting challenge to develop a general strategy that probably suitable for various lanthanide‐doped nano‐systems. Herein, we verify the cross‐relaxation possibility between sensitizer Yb3+ and activator Er3+ as well as Er3+‐ Er3+ pairs can be well modified by engineering the crystal lattice distortion of matrix, leading to the evident UC emission color variations. Specifically, with incorporating Al3+ or Ca2+ ions into the Yb/Er co‐doped BaF2 nanocrystals (NCs) contained glass ceramics (GCs), the contraction of the crystal lattice lead to the change of UC emission color from green to red. On the contrary, the high laser excitation power results in the lattice expansion of the Al3+‐doped BaF2:Yb/Er GCs at different Yb3+ concentration as well as Al3+ doped CaF2 GCs, which leads to the greatly increased green‐to‐red ratio. These multi‐color UC GCs show potential application in anti‐counterfeiting filed. Our results open up a general avenue for the control of UC emission color via engineering crystal lattice distortion. [ABSTRACT FROM AUTHOR]

Objectives: The decidua is a tissue that contacts both maternal and foetal components and is pivotal to labour onset due to its location. Due to the heterogeneity of decidual tissue, it is challenging to study its role in the peripartum period. Herein, we analysed the transcriptomes of peripartum decidua at single‐cell resolution. Materials and methods: Single‐cell RNA sequencing was performed for 29 231 decidual cells before and after delivery to characterize the transcriptomes. Results: Eight major cell types (including endothelial cells, fibroblasts) and subtypes of decidual stromal cells, extravillous trophoblasts and T cells were identified and found to have various functions. Compared with before delivery, the activation of decidual stromal cell, extravillous trophoblast and T‐cell subtypes to different degrees was observed after delivery. Furthermore, the activation involved multiple functions, such as cell proliferation, and several pathways, such as the activator protein 1 pathway. The results of pseudotemporal ordering showed differentiation of decidual stromal cell and extravillous trophoblast subtypes, suggesting inhomogeneity of these subgroups in decidualization (decidual stromal cell) and invasion (extravillous trophoblast). Conclusions: The peripartum decidual tissue is heterogeneous. This study revealed changes in the decidua and its components at single‐cell resolution; these findings provide a new perspective for the study of peripartum decidua. [ABSTRACT FROM AUTHOR]

Octahedral NaBi(WO4)2:Er3+/Yb3+ phosphors were synthesized by a hydrothermal method. Intense green upconversion emissions from both 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+ ions were observed and the appropriate energy gap between them is very suitable for temperature sensing requirement based on the fluorescence intensity ratio (FIR) technique. A flexible and portable all-fiber temperature sensing device was established and used to assess the temperature sensing characteristics of NaBi(WO4)2:Er3+Yb3+ phosphors. A maximum absolute sensitivity of 0.014 K−1 is achieved at 423 K and the temperature absolute error is −0.5 K to +0.6 K. The stepwise heating and cooling processes confirm the good stability and recyclability of the all-fiber temperature sensor, which lays the foundation for actual temperature measurement. Based on the high flexibility and accuracy of the temperature sensor, the monitoring of body temperature was realized in real time and continuously, which may provide new development prospects for effective health tracking and improvement of medical care quality. [ABSTRACT FROM AUTHOR]

Accurate and remote temperature measurements in harsh environments are of great importance. The FIR technique is self-referenced and regarded as a promising method to improve the temperature accuracy and simplify the experimental devices. Herein, a point all-fiber temperature sensor based on the FIR technique has been developed. Er3+/Yb3+ co-doped NaYF4 phosphors (NPs) were used to fabricate a temperature sensing probe combined with silica fiber. Highly crystalline and pure hexagonal NPs were synthesized by a hydrothermal method. Intense green up-conversion luminescence was observed in the prototype sensor at an excitation power of 1 mW. The relationship between FIR value and temperature was investigated at the temperature range of 258–423 K. The maximum relative temperature sensitivity is 1.68% K−1 at 258 K. Preliminary experimental results indicate that the absolute error is ±1 K with a temperature uncertainty σ of 0.187 K and relative standard deviation of 0.133%, suggesting the high accuracy and reliability of the proposed all-fiber temperature sensor. [ABSTRACT FROM AUTHOR]

Simultaneous enhancement of upconversion luminescence and temperature sensitivity is achieved by aliovalent doping in Er3+/Yb3+ codoped SrMoO4 phosphors and a highly accurate ratiometric temperature sensing platform has been constructed in an all-fiber structure. The influence of aliovalent doping of Li+ and Ga3+ in SrMoO4 phosphors on the crystal structure and growth was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A detailed structural analysis was carried out using Eu3+ ions as a spectroscopic probe to disclose the change of the local site symmetry due to aliovalent doping. The upconversion emission intensity of Er3+ in SrMoO4 phosphors is enhanced by 82 times and 255 times due to Li+ doping and Li+/Ga3+ codoping, respectively. The intense upconversion luminescence and high temperature sensitivity lead to a small temperature uncertainty (0.091 K) and an absolute error (−0.5–0.3 K) as well as good repeatability (<1%). Preliminary experiments from material design to device applications pave the way for the practical applications of ratiometric temperature sensors. [ABSTRACT FROM AUTHOR]

• The mechanism was the combined effect of electromigration and the adsorption of PANI. • Electrolytic rate was enhanced with the addition of the PANI auxiliary electrode. • PANI auxiliary electrode's particle acceleration effect was greater than adsorption. • Location of PANI auxiliary electrodes plays a crucial role in its efficacy. In this study, a polyaniline (PANI) composite supported by nonwoven fabric was synthesized and applied as an auxiliary electrode in conventional electrokinetic remediation for the first time to investigate the effectiveness of the multi-electrode system in remediating Cr-contaminated soil. Firstly, PANI was successfully combined with nonwoven fabric and has a good adsorption performance for chromium (VI) in aqueous solution, which is highly dependent on the pH of the solution. Then a series of electrokinetic experiments with four different auxiliary electrode configurations were conducted to evaluate Cr (VI) removal and its migration behavior. The results show that the Cr (VI) removal can be up to 20% higher than that of the conventional electrokinetic remediation with the existence of auxiliary electrode. And the mechanism about it was the combined effect of electromigration and the adsorption of PANI. The role of PANI auxiliary electrode was more than an adsorbent, but also an accelerator for Cr (VI) migration to the anode, which means it can intercept and adsorb the heavy metal ions passed through during strengthening the electrolysis process. The acidic environment of anode is more favorable for PANI auxiliary electrode's adsorption, but the most effective and economical arrangement about it was on the cathode side with less energy consumption of 115 kW·h/g. Because the effect of the particle acceleration of the PANI auxiliary electrode was greater than that of the adsorption. This multi-electrode system should also be applicable for the removal of anionic chemicals from contaminated soils. [ABSTRACT FROM AUTHOR]