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The present study explores the oxygen storage capacity of YBaCo4O7+δ prepared by a glycine-complex decomposition method. We reported for the first time that the YBaCo4O7+δ sample was successfully synthesized at such a low temperature of 800 °C by this method. The YBCO-800 N sample exhibited a faster oxygen absorption/desorption speed than that of high calcination temperature samples, and the time required for complete oxygen storage/release was 5 and 6 min at 360 °C, respectively. Moreover, the superior performance observed for this product in the temperature swing adsorption process makes it a promising candidate in oxygen production technologies. This research demonstrated that the glycine-complex decomposition method is an effective method for improving the oxygen storage property of YBaCo4O7+δ and provides a new insight into designing other novel oxygen storage materials.

In this study, to clarify the corrosion mechanism of CA6 based refractory by refining slag, the static crucible tests for CA6, CA6-Al2O3, and Al2O3 refractory, were carried out and the detail reaction processes were analyzed from the perspective of thermodynamic simulation and structural evolution. From the results, CaAl4O7 plays a vital role in the slag corrosion resistance of the three refractories. Regarding CA6 refractory, the double pyramid module in CA6 crystal structure was destroyed very quickly, leading to the rapid collapse of its structure to form the denser CaAl4O7 in high amounts. As a result, a reaction layer mainly composed of CaAl4O7 formed, which effectively inhibited the slag corrosion, so CA6 refractory exhibits the most excellent slag corrosion. Meanwhile, the formation of CaAl4O7 can also avoid CA6 particles entering the molten steel to introduce exogenous inclusions. For Al2O3 refractory, the generation of CaAl4O7 is much slower than that of CA6 and CA6-Al2O3 refractory, and the amount generated is also quite small, resulting in its worst slag corrosion among the three crucibles. Therefore, CA6 based refractory has excellent application potential in ladle refining and clean steel smelting.

Objective: To identify an optimal magnetic resonance imaging-based classification for evaluating the efficacy of focused ultrasound ablation surgery (FUAS). Design：A retrospective cohort study. Setting: The Affiliated Nanchong Central Hospital of North Sichuan Medical College, Nanchong, Sichuan, China. Population: A total of 643 adenomyosis patients who received FUAS from June 2017 to December 2021. Methods: One-way ANOVA test and chi square test were used to identify an optimal classification for evaluating FUAS efficacy. Magnitude of the optimal classification relating to timing of recurrence in FUAS group was measured by cox regression with hazard ratio (HR) and 95% CI. K-M curve was applied to estimate the medium recurrence time of adenomyosis in the optimal classification. Main outcome measures: The identification of different classifications for FUAS efficacy and the factors contributing to recurrence after FUAS. Results: The rates of dysmenorrhea relief (χ2=10.079, P=0.018) and recurrence could be identified by classification 2 in FUAS group (χ2=10.582, P=0.014), but not in FUAS+ group (P＞0.05). Besides, the recurrence rate in FUAS group (22.2.0%) was higher than that in FUAS+ group (12.1%). Extrinsic subtype in classification 2 (HR=2.315, 95% CI 1.219～4.560, P=0.011) correlated to recurrence of adenomyosis in FUAS group. K-M curve showed that the medium recurrence time of extrinsic subtype (45.2 months) was shorter than that of other subtypes (52.0 months). Conclusions: Classification 2 was the optimal one to identify the rates of dysmenorrhea relief and recurrence. Extrinsic subtype was related to the earlier onset of recurrence after FUAS.

Lanthanide-substituted YMnO3+δ nanoparticles with the hexagonal phase, denoted as R0.25Y0.75MnO3+δ (R = Er, Dy, Tb, Gd, and Sm), have been successfully synthesized by the polymerized complex method. The substitutions did not largely affect the morphologies and specific surface area of the obtained R0.25Y0.75MnO3+δ nanoparticles. From the evaluation for the oxygen storage/release properties, the oxygen storage capacity (OSC) increased significantly by the Tb substitution, and the oxygen absorption/release rate strongly depended on the ion size of the substituted lanthanides. It was found that Tb4+ existed in Tb0.25Y0.75MnO3+δ after oxygen absorption, demonstrating that the remarkable increase in the OSC of the Tb-substituted sample was due to the oxidation of not only Mn3+ to Mn4+ but also Tb3+ to Tb4+. In addition, the unit cell volume increasing with the R ion size, which can lead to the promotion of the oxygen diffusion in the crystal structure, was the factor leading to the increase of the oxygen absorption rate. Especially, Sm0.25Y0.75MnO3+δ showed an excellent OSC of 3 + δ = 3.34 (the weight increase rate was 2.64 wt %) even under a rapid temperature swing rate of 20 °C/min.

Acetone, as widely used reagents in industry and laboratories, are extremely harmful to the human. So the detection of acetone gas concentrations and leaks in special environments at room temperature is essential. Herein, the nanocomposite combining SnO-SnO2 (p-n junction) and Ti3C2Tx MXene was successfully synthesized by a one-step hydrothermal method. Because of the existence of a small amount of oxygen during the hydrothermal conditions, part of the p-type SnO was oxidized to n-type SnO2, forming in-situ p-n junctions on the surface of SnO. The hamburger-like SnO-SnO2/Ti3C2Tx sensor exhibited improved acetone gas sensing response of 12.1 (Rg/Ra) at room temperature, which were nearly 11 and 4 times higher than those of pristine Ti3C2Tx and pristine SnO-SnO2, respectively. Moreover, it expressed a short recovery time (9 s) and outstanding reproducibility. Because of the different work functions, the Schottky barrier was formed between the SnO and the Ti3C2Tx nanosheets, acting as a hole accumulation layer (HALs) between Ti3C2Tx and tin oxides. Herein, the sensing mechanism based on the formation of hetero-junctions and high conductivity of the metallic phase of Ti3C2Tx MXene in SnO-SnO2/Ti3C2Tx sensors was discussed in detail.