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Some inherent characteristics of thermal barrier coatings (TBC), such as porosity, thinner thickness and relatively high electrical resistivity, limit the application of traditional room temperature non-destructive testing techniques.Therefore, a method for monitoring oxide growth in thermal barrier coatings using impedance spectroscopy in high-temperature environments was proposed.Based on the principle of impedance spectroscopy test, the growth information of oxides in thermal barrier coatings was obtained by analyzing the response of AC impedance in different frequency domains and phase angle information, and the prediction model was constructed based on the micromorphology of SEM.Results showed that after oxidizing at 1 000 ℃for different times, a dense dark thermally grown oxide (TGO) layer was formed between the ceramic layer and the adhesive layer, and its thickness increased with the prolongation of oxidation time, exhibiting a non-linear relationship.As the oxidation time prolonged, the composition of the TGO layer transitions from Al2O3 in the early stage of oxidation to a mixed oxide of Al2O3 (mainly), Cr2O3, CoO and NiO.Furthermore, the relationship between the resistance of the TGO layer and the oxidation time was constructed by establishing an appropriate circuit model to fit the impedance spectrum data, which confirmed the feasibility of non-destructive testing using impedance testing technology in the process of high-temperature degradation of thermal barrier coatings.

α‐Tertiary primary amines (α‐TPAs) bearing a fully substituted carbon center adjacent to the N‐unsubstituted amino group (−NH2) exhibit unique biochemical and physicochemical activities. While due to the sterically congested structure and strong nucleophilic and alkaline natures of these primary amine compounds, their facile synthesis remains an inherent challenge. Traditional methods commonly rely on tedious N‐protection/deprotection operations and highly reactive organometallic reagents, thus leading to poor atom and step‐economy and limited functional group compatibility. Modern photoredox catalysis offers a robust tool to prepare such structurally unique and synthetically valuable amine architectures via a radical pathway under extremely mild conditions. In this review, the recent progress in photocatalytic synthesis of α‐TPAs is systematically reviewed, and the reaction scope, limitations, and mechanisms for the reactions are discussed. [ABSTRACT FROM AUTHOR]

The reliability and efficiency of the grounding system in substations is of utmost importance for the safety of the electrical grid. In China, the grounding grids of substations are primarily composed of galvanized steel, carbon steel, and copper, all of which are susceptible to corrosion from soil during operation. This study thoroughly examines the effects of typical Cl− ions and soil water content on the corrosion behavior of a Q235 steel in situ. The data suggest that there is a negative correlation between soil moisture and grounding grid corrosion, whereas dissolved salts, particularly Cl− ions in soil, correlate positively. [ABSTRACT FROM AUTHOR]

Inflammation plays a critical role in the development of severe neonatal morbidities. Myeloid-derived suppressor cells (MDSCs) were recently implicated in the regulation of immune responses in newborns. Here, we report that the presence of MDSCs and their functional activity in infants are closely associated with the maturity of newborns and the presence of lactoferrin (LF) in serum. Low amounts of MDSCs at birth predicted the development of severe pathology in preterm infants--necrotizing enterocolitis (NEC). In vitro treatment of newborn neutrophils and monocytes with LF converted these cells to MDSCs via the LRP2 receptor and activation of the NF-[kappa]B transcription factor. Decrease in the expression of LRP2 was responsible for the loss of sensitivity of adult myeloid cells to LF. LF-induced MDSCs (LF-MDSCs) were effective in the treatment of newborn mice with NEC, acting by blocking inflammation, resulting in increased survival. LF-MDSCs were more effective than treatment with LF protein alone. In addition to affecting NEC, LF-MDSCs demonstrated potent ability to control ovalbumin-induced (OVA-induced) lung inflammation, dextran sulfate sodium-induced (DSS- induced) colitis, and concanavalin A-induced (ConAinduced) hepatitis. These results suggest that cell therapy with LF- MDSCs may provide potent therapeutic benefits in infants with various pathological conditions associated with dysregulated inflammation., Introduction Early life, especially the first weeks after birth, is characterized by high vulnerability to infection and inflammation-mediated tissue injury. Dysregulation of inflammatory responses and host-microbial interactions play a central [...]

Bridged benzazepine scaffolds, possessing unique structural and physicochemical activities, are widespread in various natural products and drugs. The construction of these skeletons often requires elaborate synthetic effort with low efficiency. Herein, we develop a simple and divergent approach for constructing various bridged benzazepines by a photocatalytic intermolecular dearomatization of naphthalene derivatives with readily available α‐amino acids. The bridged motif is created via a cascade sequence involving photocatalytic 1,4‐hydroaminoalkylation, alkene isomerization and cyclization. Interestingly, the diastereoselectivity can be regulated through different reaction modes in the cyclization step. Moreover, aminohydroxylation and its further bromination have also been demonstrated to access highly functionalized bridged benzazepines. Preliminary mechanistic studies have been performed to get insights into the mechanism. This method provides a divergent synthetic approach for construction of highly functionalized bridged benzazepines, which have been otherwise difficult to access. [ABSTRACT FROM AUTHOR]

Gasoline is a globally used primary fuel. The submicron particles at gasoline stations have not been extensively investigated. This study aimed to evaluate the exposure concentrations and inhalation risk of submicron particles at a gasoline station. Temporal variations in particle concentrations and size distributions were measured using a real-time system. The effective doses of submicron particles deposited in different organs were analyzed using a computational fluid dynamics model and the value of environmental monitoring (including the size distributions of particles by number). The number concentration (NC) was higher during working hours than that of the background. Submicron particles gathered predominantly at 30.5 nm and 89.8 nm during working time. The effective doses of submicron particles deposited in the olfactory system and lungs were 0.131 × 10−3 and 0.014 mg, respectively, of which 0.026 × 10−3 mg potentially reached the brain. In a female worker with 3 years of exposure, the average daily effective doses in the olfactory system, lungs, and brain were 2.19 × 10−7 mg/kg·d−1, 2.34 × 10−5 mg/kg·d−1, and 4.35 × 10−8 mg/kg·d−1, respectively. These findings indicated that workers at this gasoline station had a high inhalation risk of submicron particles. This study provides baseline data on submicron particles at gasoline stations and a critical basis for investigating disease risk in longitudinal epidemiological studies. [ABSTRACT FROM AUTHOR]