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The bonding strength and LBE corrosion resistance of the Fe15Cr11Al2Si, Fe15Cr11Al0.5Y, and Fe15Cr11Al2Si0.5Y coatings heat‐treated at 500–650°C for 500 h were investigated. The results showed that the as‐deposited Fe15Cr11Al0.5Y coating has the strongest bonding strength with the F/M steel cladding tube compared with the Fe15Cr11Al2Si and Fe15Cr11Al2Si0.5Y coatings. Heat treatment deteriorates the bonding performance of the coatings, and obvious enrichment of Cr and Al elements appeared. The consumed Al element inside the heat‐treated coatings promotes the formation of Fe3O4 on the surface of the coatings after the corrosion test. The Y element can inhibit the enrichment of elements and the formation of Fe3O4. The bonding strength of the heat‐treated coatings can be improved after the corrosion test. The underlying mechanism of the evolution of microstructure and properties of the coatings after heat treatment and corrosion test was discussed. [ABSTRACT FROM AUTHOR]

Ni-20Cr-Eu2O3 composites were designed as new control rod materials and were synthesized from Ni, Cr, and Eu2O3 mixture powders via ball milling and vacuum hot pressing. During ball milling, Eu2O3 was fined, nano-crystallized, amorphized, and then dissolved into matrix. The effect of Eu2O3 content on the microstructure and mechanics was researched, and the corresponding mechanism was discussed. The relative densities, grain sizes, and microhardness increased when Eu2O3 content increased. According to the TEM observations, Eu2O3 particles showed a semi-coherent relationship with the matrix. The results of mechanical property testing showed that the ultimate tensile strength, yield strength, and elongation decreased with the Eu2O3 content increased. The maximum ultimate tensile strength, yield strength, and elongation were 741 MPa, 662 MPa, and 4%, respectively, with a 5 wt.% Eu2O3 addition. The experimental strengths were well matched with the theoretical values calculated by the strengthening mechanisms indicating that this method was highly effective for predicting the mechanical properties of Ni-20Cr-Eu2O3 composites. [ABSTRACT FROM AUTHOR]

Cover:Surface morphology of the coatings corroded at 650 °C for 500 h. (a) – (a3) Fe15Cr11Al2Si coating; (b) – (b3) Fe15Cr11Al0.5Y coating; (c) – (c3) Fe15Cr11Al2Si0.5Y coating. The red numbers represent the position of the elemental point analysis.Wei Zhang, Mingyang Zhou, Huifang Yue, Danmin Peng, Xi Qiu, Jijun Yang, Effect of heat treatment on the microstructure, LBE corrosion resistance, and bonding strength of the FeCrAl‐based coatings, Materials and Corrosion 2024, 75, 1406..By Wei Zhang; Mingyang Zhou; Huifang Yue; Danmin Peng; Xi Qiu and Jijun YangReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

MAX phases are promising candidate structural materials for lead-cooled fast reactors (LFRs) and accelerator-driven sub-critical systems (ADSs) due to their excellent corrosion resistance in liquid LBE. In this work, one of the typical MAX phases, Ti3SiC2, was exposed to the flowing LBE with a saturated oxygen concentration at 500 °C for up to 3000 h. The corrosion behaviors, including the evolution of the corrosion layer, mechanical properties and wettability, were evaluated via X-ray diffraction, a scanning electron microscope equipped with an energy-dispersive X-ray, a microhardness test and contact angle measurement. The results reveal that a corrosion structure with a duplex layer was formed on the sample surfaces. The outer layer was a diffusion layer, which always remained thin (<3 μm) during the whole test due to the erosion effect caused by the flowing LBE. The inner layer was the stable protective oxide layer, and its thickness increased with exposure time. The growth of the corrosion structure improved the microhardness and reduced the wettability with regard to LBE, which was beneficial to inhibiting further surface corrosion of Ti3SiC2. [ABSTRACT FROM AUTHOR]

Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts' surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results. [ABSTRACT FROM AUTHOR]

To optimize the simultaneous removal of NOx and Hg0, a series of CuaCebZrcO3/γ-Al2O3 catalysts prepared by the impregnation method were explored and their physical and chemical properties were analyzed by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), NH3-temperature-programmed desorption (NH3-TPD), H2-temperature-programmed reduction (H2-TPR), in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFT), and Fourier transform infrared spectroscopy (FT-IR). The results showed that 15% Cu1.4Ce0.55Zr0.25O3/γ-Al2O3 resulted in the highest conversion efficiency for the simultaneous removal of NOx (93%) and Hg0 (85%) at low temperatures (200 to 300 °C). Meanwhile, 15% Cu1.4Ce0.55Zr0.25O3/γ-Al2O3 showed good stability and resistance to SO2 and H2O, which is due to its low crystallinity, good textural performance, and strong redox ability. According to the TPD, TPR, and XPS results, the strong acidic character of 15% Cu1.4Ce0.55Zr0.25O3/γ-Al2O3 promoted the removal of NOx and Hg0. The synergistic effect between CuO and CeO2 in 15% Cu1.4Ce0.55Zr0.25O3/γ-Al2O3 can increase the mobility of chemically adsorbed oxygen and activates lattice oxygen, leading to an excellent performance. The DRIFT results showed that NH3, NH4+, nitrate, and nitrite participated in the selective catalytic reduction (SCR) reaction. On the basis of our experimental results, Hg0 and NOx removal mechanisms were proposed as Hg (ad) + O* → HgO (ad) and 2NH3/NH4+ (ad) + NO2/NO3− (ad) + NO→2N2 + 3H2O/2H+, respectively. [ABSTRACT FROM AUTHOR]

The growth kinetics of microarc oxidation TiO2 ceramic film on Ti6Al4V alloy in 0.1 M Na2B4O7·10H2O electrolyte were studied using scanning electron microscopy, transmission electron microscope, atomic force microscope, X-ray diffraction, and potentiodynamic polarization. It was found that the discharge sizes increased gradually from anodic oxidation, spark discharge, and microarc to arc discharges in the microarc oxidation process, and reached the maximum value without anymore increases. The microarc oxidation coating was mainly composed of nanocrystalline rutile TiO2 grains with very little amorphous titanium dioxide, and was made up of three layers, namely an inner dense thin layer, a middle dense thick layer, and a porous outer layer. The content of the rutile phase increased with the increasing discharge size, and when the discharge size reached a maximum, the increase rate decreased slightly. The surface roughness, Rv, and corrosion resistance of the coating increased with the increasing discharge size until the discharge size reached a maximum. It was concluded that the thickness of two dense layers depended on the discharge size, with any changes in it revealing the growth kinetics of the coating. A new method was developed to obtain the effective thickness of the coatings by measuring the thickness of the two dense layers. The results demonstrated that the growth kinetics of the two dense layers are linear during spark and microarc discharges, of which the growth trend is the same as that of the voltage. A linear relationship for the voltage and thickness of the two dense layers was obtained. [ABSTRACT FROM AUTHOR]

In this study, series of CexZryMnzO2/r-Al2O3 catalysts were prepared by impregnation method and explored to co-purification of NOx and Hg0 at low temperature. The physical and chemical properties of the catalysts were investigated by XRD, BET, FTIR, NH3-TPD, H2-TPR, and XPS. The experimental results showed that 10% Ce0.2Zr0.3Mn0.5O2/r-Al2O3 yielded higher conversion on co-purification of NOx and Hg0 than the other prepared catalysts at low temperature, especially at 200-300 °C. 91% and 97% convert rate of NOx and Hg0 were obtained, respectively, when 10% Ce0.2Zr0.3Mn0.5O2/r-Al2O3 catalyst was used at 250 °C. Moreover, the presence of H2O slightly decreased the removal of NOx and Hg0 owing to the competitive adsorption of H2O and Hg0. When SO2 was added, the removal of Hg0 first increased slightly and then presented a decrease due to the generation of SO3 and (NH4)2SO4. The results of NH3-TPD indicated that the strong acid of 10% Ce0.2Zr0.3Mn0.5O2/r-Al2O3 improved its high-temperature activity. XPS and H2-TPR results showed there were high-valence Mn and Ce species in 10% Ce0.2Zr0.3Mn0.5O2/r-Al2O3, which could effectively promote the removal of NOx and Hg0. Therefore, the mechanisms of Hg0 and NOx removal were proposed as Hg (ad) + [O] → HgO (ad), and 2NH3/NH4+ (ad) + NO2 (ad) + NO (g) → 2 N2 + 3H2O/2H+, respectively.ᅟ [ABSTRACT FROM AUTHOR]

Simultaneous oxidation of Hg0 and NH3-SCR of NO by catalyst is one of the key methods for co-purification of coal-fired flue gas. Till now, the interaction between the oxidation of Hg0 and NH3-SCR of NO and its mechanism have not clarified. In this study, a series of nanophase CexZryMnzO2 was prepared for the simultaneous oxidation of Hg0 and NH3-SCR of NO at low temperature. The catalysts were characterized using surface area analysis, X-ray diffraction, temperature-programmed techniques, and several types of microscopy and spectroscopy. The experimental results indicated that the Ce0.47Zr0.22Mn0.31O2 exhibited superior Hg0 removal efficiency (> 99%) and NO conversion efficiency (> 90%) even at 150 °C, and it also exhibited a good durability in the presence of SO2 and H2O. The excellent performance of Ce0.47Zr0.22Mn0.31O2 on co-purifying Hg0 and NO was due to the stronger synergistic effects of Ce-Zr-Mn in Ce0.47Zr0.22Mn0.31O2 than that of the others, which was illustrated by the characterization results of XPS, XRD, and FT-IR. Moreover, it was found that the NO conversion of Ce0.47Zr0.22Mn0.31O2 could be slightly influenced by Hg0 and was decreased about 4% to the max, while that of Hg0 could rarely be affected by the selected catalytic reduction process of NO. It might be due to the co-purification mechanism of NO and Hg0. The mechanism of the simultaneous oxidation of Hg0 and NH3-SCR of NO was mainly due to the synergetic effect on the mobility of surface oxygen and the activation of lattice oxygen of Ce0.47Zr0.22Mn0.31O2. The effect of the oxidation of Hg0 on the NH3-SCR of NO was mainly due to the absorbed Hg0/Hg2+ on the surface of Ce0.47Zr0.22Mn0.31O2, which attenuated the formation of NH3(ad), −NH2(ad), and NH4+ on its acid sites. Similarly, the NH3-SCR of NO process could hardly influence the oxidation of Hg0 when NO and Hg0 were co-purified. [ABSTRACT FROM AUTHOR]

To investigate the etiologies and clinical characteristics of full-thickness macular hole (FTMH) cases at Shanxi Eye Hospital in North China. Patients diagnosed with FTMH who underwent surgery from 2012 to 2020 were included, and the etiologies and clinical features of MH types were analyzed in an 8-year, cross-sectional, retrospective study. A total of 752 cases (776 eyes) were analyzed. The top 3 subtypes of MH were idiopathic (IMH, 64.4%), myopic (MMH, 21.1%) and traumatic (TMH, 3.7%) MH. Among these, there were significant differences in sex, age, and baseline best-corrected visual acuity (BCVA) distributions. Females predominated in the IMH and MMH groups, while males predominated in the TMH group. The IMH onset age was older than the MMH and TMH onset ages. Baseline BCVA in the IMH (Z = 8.9, P < .001) and the other group (Z = 4.0, P < .001) was significantly better than that in the MMH group. In the IMH group, females were younger, had a shorter axial length (AL), and had a worse baseline BCVA than males, while in the MMH group, there were no significant sex differences. Multivariate correlation analysis showed that a smaller hole diameter in IMH, no retinal detachment in MMH, and a younger age in TMH may result in better baseline BCVA. The most common MH etiologies were IMH, MMH and TMH, which contributed to differences in clinical features. Females predominated in the IMH and MMH groups, and the onset of MMH occurred 6.5 years earlier than the onset of IMH. Therefore, early fundus monitoring in females and high myopia patients is helpful for the early detection and treatment of MH., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Vitrectomy combined with internal limiting membrane (ILM) peeling or ILM inverted flap greatly improves hole closure and vision prognosis for idiopathic macular holes (IMH). The application of indocyanine green (ICG) in MH surgery increases the visibility of ILM and the safety of surgery. However, the area of ILM peeling and the state of the flap and a closed hole has not been well observed., Aim: Fundus autofluorescence at 7935nm can show the range of ILM peeling and the state of the hole site and ILM flap by monitoring residual ICG postoperatively. However, the characteristics of fundus autofluorescence especially the site of the closed hole, and its relationship with vision prognosis have not been explored. The aim of this project was to find the autofluorescence features of the closed hole and their relation with vision., Objective: To investigate the characteristics of fundus autofluorescence imaging after ICG-assisted vitrectomy for IMH and to evaluate the correlations of fluorescence patterns at the MH site with visual acuity and macular anatomic outcomes., Methods: We retrospectively evaluated 33 IMH patients (33 eyes) who underwent a 25G pars plana vitrectomy (follow-up, 6-14.5 months). ICG staining (2.5 mg/mL) was either used to remove the internal limiting membrane (ILM) or the inverted ILM flap was overlaid on the hole. After surgery, fluorescence imaging of the fundus was obtained using a scanning laser ophthalmoscope at 795 nm., Results: On fluorescence imaging, the area of ILM peeling in all eyes showed hypofluorescence with no changes over time. The inverted ILM flap (performed in 18 eyes) was positioned on the inferior retina and exhibited early mild hyperfluorescence with blurred edges. This was gradually enhanced up to 3-6 months postoperatively and was then attenuated. MHs showed two distinct patterns on optical coherence tomography: granular (21 eyes) and patchy hyperfluorescence (12 eyes). Best-corrected visual acuity improved postoperatively in all cases (p<0.001, Z=-4.744). VA was worse in the patchy (vs. granular) hyperfluorescence cases (p=0.011, Z=-2.548)., Conclusion: The status of the ILM peeling area, ILM flap, and closed MH can be clearly observed using autofluorescence imaging at 795 nm. Fluorescence may be due to ICG staining of the ILM and accumulation in retinal pigment epithelium cells during ICG-assisted surgery. Granular hyperfluorescence at the MH site may indicate good anatomic and visual prognoses., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)