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Gas-filled bubbles present significant challenges in materials as they make materials porous and weaken the strength of materials. Here, argon bubbles that are formed during the fabrication of oxide dispersion strengthened (ODS) steels are investigated. The Ar bubbles are attached to nano-oxides which are dispersed in the matrix. MA956 ODS specimen was irradiated with 362 MeV 129Xe26+ at room temperature to about 7 dpa at peak damage. The behavior of Ar bubbles in different irradiation depths was investigated by using transmission electron microscopy (TEM) via cross-section specimens. The results show that Ar-bubbles in the peak damage and ions deposition region experience an apparent dissolution. Further, we simulate the behavior of isolated Ar bubble and attached Ar bubble to oxide under primary knock-on atoms (PKA) with different energy and numbers by using molecular dynamics (MD). The results show that high energy PKA (exceeding 30 keV) and multiple cascades can contribute to the effective ejection of Ar atoms from bubbles. Meanwhile, the interface between oxide and bubble contributes less to the bubble dissolution. Besides that, the effects of thermal ejection and excess self-interstitial atoms generated from the implantation of foreign atoms on the dissolution of Ar bubbles are discussed.

We use a sample of Chinese firms from 2006 to 2020 to investigate the effect of information infrastructure on the quality of green innovation. Findings show that information infrastructure significantly improves corporate green innovation quality, and information infrastructure improves the pricing efficiency, improves valuation levels, accelerates the flow of innovation resources, and induces the growth effect of corporate innovation resources. Furthermore, we find that executive salary incentives, internal control quality, and market-oriented environmental regulation have adaptive incentives for information infrastructure to improve the quality of green innovation. Our findings provide justification to promote the construction of an information infrastructure and adopt market-oriented environmental regulations to improve corporate green innovation quality.

As the essential equipment in ultra-high voltage direct current transmission systems, converter transformers provide an important role in the stable operation of the power grid. During the long-term operation of converter transformers, the aging and decomposition of the oil-paper insulation cause a great quantity of metal and non-metal solid particles in the transformer oil, which is one of the important reasons for the equipment failure. The solid particles are affected by various forces in transformer oil, among which the Coulomb force dominates their motion characteristics. The charging process of solid particles contacting the electrode is very important. There are many discussions on the charge carried by metal particles after colliding with the electrode, but less research on the Coulomb force of non-metallic particles in the oil. A simulation model is established to calculate the Coulomb force of metal and non-metal particles in the oil, and the moving process of spherical solid particles of different diameters under different voltages is observed. The research shows that for spherical solid particles with the same material, the Coulomb force increases non-linearly with the increase of particle size. For particles with different materials of the same particle size, the Coulomb force experienced by metal particles is relatively large. Therefore, the charge carried by non-metal particles after colliding with the electrode cannot be calculated by the charge calculation method of metal particles. The research is helpful to analyze the force and movement process of particles in oil and provides support for transformer fault diagnosis and insulation structure design.

The main factors affecting the performance of solid acid catalyzed liquid-phase condensation of aniline to diphenylamine are acidity and pore structure. Fluorine has strong electron affinity due to its special electronic structure, which can adjust the acidity and pore structure of zeolite. β zeolite was modified with different concentrations of NH4F solution. The aluminum in the framework of aluminosilicate zeolite was removed to a certain extent, and the acidity and pore size of β zeolite were controlled. Combined with XRD, Py-IR, Al MAS NMR and DRIFTS the active center and reaction mechanism of the catalytic reaction were discussed.

Antimicrobial resistance is an increasingly serious threat to public health worldwide. The presence of antibiotic resistance genes (ARGs) in human airways and relevant environments has not received significant attention. In this study, abundances of ARGs and microbes from airborne particulate matter, dust, and human airways in a hospital were profiled using high-throughput qPCR and 16S rRNA gene sequencing. More diverse ARGs and microbes in indoor dust and higher levels of ARGs in particulate matter PM10 and PM2.5 were observed. Macrolides and aminoglycoside resistance genes were the most abundant ARGs in the airway and environmental samples, respectively. Moreover, the co-occurrences of priority pathogens, ARGs, and mobile genetic elements (MGEs) were shown by the Network analysis. Campylobacter spp. and Staphylococcus spp. positively correlated with fluoroquinolone (vatC-02, mexD) and β-lactams (blaZ, mecA) resistance genes, respectively. In this regard, based on SourceTracker analysis, inhalable particles contributed to 4.0% to 5.5% of ARGs in human airway samples, suggesting an important exchange between airborne inhalable particles and human commensals. This study may advance knowledge about ARGs in airborne particulate matter and dust associated environments, reveal their potential link between environments and humans, and provide a new sight and fundamental data for ARG risk assessment.

In this work, sulfated zirconia (SZ) was prepared by a solvent-free method, ammonium sulfate ((NH4)2SO4) and sulfamic acid (NH2SO3H) were as sulfur sources, respectively. The resulting catalysts were characterized by powder X-ray diffraction (XRD), thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), N2 adsorption–desorption isotherms, inductively coupled plasma (ICP) and pyridine-FTIR. The characterization of the catalysts revealed that SZ prepared with (NH4)2SO4 as sulfur source contained more Lewis acid sites and less Brønsted acid sites. The effects of sulfur sources on the catalytic activity of catalysts were studied. Catalytic testing showed that SZ prepared with (NH4)2SO4 as sulfur source had a better catalytic performance for removing trace olefins from aromatics. Keywords: Aromatics, Olefins, Sulfur sources, Sulfated zirconia

Upward flame spread characteristics over extruded polystyrene (XPS) foams with different porosities has been analyzed through experiments. In this paper, the average flame height and average maximum flame temperature first rise and then drop with increasing porosity, which is affected by the fuel and oxygen competition mechanisms. For P (the porosity of XPS samples) ≤ 35%, the positive effect of pores plays a dominant role; the average flame height and average maximum flame temperature increase with the increasing porosity. While the negative effect of pores plays a dominant role when P > 35%, causing the average flame height and average maximum flame temperature decrease with the increasing porosity. Modeling and experiments were conducted to study the heat flux from flame. The value of radiation is obviously higher than convection through formula derivation and the experimental results have high similarity with the theoretical results. Keywords: XPS, Porosity, Upward flame spread characteristics, Heat transfer

Purpose: To evaluate longitudinal changes in macular choroidal thickness (mCT) in myopic children treated for 1 year with repeated low-level red-light (RLRL) therapy and their predictive value for treatment efficacy on myopia control., Design: A secondary analysis of data from a multicenter, randomized controlled trial (RCT; NCT04073238)., Participants: Myopic children aged 8-13 years who participated in the RCT at 2 of 5 sites where mCT measurements were available., Methods: Repeated low-level red-light therapy was delivered using a home-use desktop light device that emitted red-light at 650 nm. Choroidal thickness was measured by SS-OCT at baseline and 1-, 3-, 6-, and 12-month follow-ups. Visual acuity, axial length (AL), cycloplegic spherical equivalent refraction (SER), and treatment compliance were measured., Main Outcome Measures: Changes in mCT at 1, 3, 6, and 12 months relative to baseline, and their associations with myopia control., Results: A total of 120 children were included in the analysis (RLRL group: n = 60; single-vision spectacle [SVS] group: n = 60). Baseline characteristics were well balanced between the 2 groups. In the RLRL group, changes in mCT from baseline remained positive over 1 year, with a maximal increase of 14.755 μm at 1 month and gradually decreasing from 5.286 μm at 3 months to 1.543 μm at 6 months, finally reaching 9.089 μm at 12 months. In the SVS group, mCT thinning was observed, with changes from baseline of -1.111, -8.212, -10.190, and -10.407 μm at 1, 3, 6, and 12 months, respectively. Satisfactory myopia control was defined as annual progression rates of less than 0, 0.05, or 0.10 mm for AL and less than 0, 0.25, or 0.50 diopters for SER. Models that included mCT changes at 3 months alone had acceptable predictive discrimination of satisfactory myopia control over 12 months, with areas under the curve of 0.710-0.786. The predictive performance of the models did not significantly improve after adding age, gender, and baseline AL or SER., Conclusions: This analysis from a multicenter RCT found RLRL induced sustained choroidal thickening over the full course of treatment. Macular choroidal thickness changes at 3 months alone can predict 12-month myopia control efficacy with reasonable accuracy., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., (Copyright © 2022 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Vascular peroxidase 1 (VPO1) plays a key role in mediation of cardiovascular oxidative injury. This study aims to determine whether VPO1 can promote programmed necrosis of endothelial cells and the underlying mechanisms., Methods and Results: Human umbilical vein endothelial cells (HUVECs) were incubated with oxidized low-density lipoprotein (ox-LDL, 100 μg/mL) for 48 h to induce cell injury, which showed an elevation in cell necrosis (reflected by the increased propidium iodide (PI) positive-staining cells, LDH release and decreased cell viability), concomitant with an increase in programmed necrosis-relevant proteins including receptor-interacting protein kinase 1/3 (RIPK1/3), p-RIPK3 and mixed lineage kinase domain like (MLKL); these phenomena were attenuated by necrostatin-1(Nec-1) and RIPK3 siRNA. Meanwhile, VPO1 was up-regulated in ox-LDL-treated endothelial cells accompanied by a decrease in GSK-3β activity and p-β-catenin levels, and an elevation of β-catenin levels; these phenomena were reversed in the presence of VPO1 siRNA or hypochlorous acid (HOCl) inhibitor; replacement of ox-LDL with HOCl could also induce endothelial programmed necrosis and activate the β-catenin signaling; β-catenin inhibitor could also suppress ox-LDL-induced RIPK-dependent necrosis. In hyperlipidemic patients, the plasma level of VPO1 was obviously increased concomitant with an elevation in plasma levels of RIPK1, RIPK3 and MLKL, and they were positively correlated., Conclusions: VPO1 plays an important role in promotion of endothelial programmed necrosis under hyperlipidemic conditions through activation of β-catenin signaling. It may serve as a novel therapeutic target for prevention of endothelial dysfunction in hyperlipidemia., (Copyright © 2018 Elsevier B.V. All rights reserved.)