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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.

This study was conducted in order to explore the effect of exogenous glucose treatment on postharvest cold resistance and sugar metabolism in apricot fruit. Xinjiang-grown ‘Saimati’ apricots were subjected to vacuum osmosis treatment with different concentrations of glucose followed by cold storage at (0 ± 1) ℃ for 49 days. The incidence of chilling injury, chilling injury index, quality and sugar metabolism-related indicators of apricot fruit were measured at regular intervals during the storage period. The results showed that 200 mmol/L exogenous glucose treatment could effectively inhibit the increase in the incidence of chilling injury, chilling injury index, cell membrane permeability and the accumulation of malondialdehyde (MDA), and well maintain the hardness, color, soluble solids content (SSC), titratable acid (TA) and ascorbic acid (ASA) contents of apricot fruit. Meanwhile, compared with the control group, the exogenous glucose treatment increased the activities of acid invertase (AI), neutral invertase (NI), sucrose phosphate synthase (SPS) and sucrose synthase (SS) in apricot fruit, and significantly increased the accumulation of glucose and fructose during storage. However, the content of sucrose decreased during the mid-to-late stage of storage (21–49 days). In summary, exogenous glucose treatment could enhance the contents of glucose and fructose by regulating the activity of enzymes related to sugar metabolism, thereby enhancing cold resistance and maintaining the storage quality of the fruit. The results of this study can provide a reference for controlling chilling injury in postharvest apricot fruit.

The stability of Pickering emulsion stabilized by solid lipid particles (SLPs) is directly impacted by changes in its crystal structure. The mechanism behind the effect of changes in the crystal structure of palm stearin (PS) as an ideal raw material for SLPs on Pickering emulsion stability is still unknown. In this study, PS-SLPs with different crystalline structures (size, crystal shape and morphology) (T40-PS-SLPs and SC-PS-SLPs) were prepared by adding 0.5%–5% of Tween 40 (T40) or sodium caseinate (SC), and oil-in-water (O/W) Pickering emulsion stabilized by SLPs was successfully constructed. Moreover, the relationship between the crystalline structure of the PS-SLPs and the stability of O/W Pickering emulsion stabilized by them was investigated. The findings indicated that most T40-PS-SLPs were lath-like particles with a particle size range of 124.1–370.1 nm, and the major crystal structure was type β’, while SC-PS-SLPs were type β’ irregular spherical particles with a particle size range of 309.7–346.2 nm. After sonication, both T40-PS-SLPs and SC-PS-SLPs wrapped 10% corn oil to form stable O/W Pickering emulsion; the average droplet size of the emulsion prepared with T40-PS-SLPs ranged from 0.76 to 2.23 μm and the lipid crystals in the emulsion were predominantly type β, while the emulsion prepared with SC-PS-SLPs showed average droplet sizes ranging from 0.81 to 1.27 μm and most lipid crystals were type β’. It was found that during the preparation of Pickering emulsion, the crystal form of T40-PS-SLPs changed from sub-stable type β’ to stable type β, while the crystal form of SC-PS-SLPs did not change significantly. After 60 days of storage, it was found that the Pickering emulsion prepared with T40-PS-SLPs containing more than 1% of T40 and that prepared with SC-PS-SLPs containing more than 1% of SC were stable for at least 30 days. Overall, the emulsion prepared with type-β’ irregular lath-like T40-PS-SLPs with small particle size showed better storage stability. This study provides some data support for the development of O/W Pickering emulsion stabilized by lipid-based solid particles.

The Domain of Unknown Function 506 (DUF506) belongs to the PD-(D/E) XK nuclease superfamily and has been reported to play critical roles in growth and development as well as responses to abiotic stresses. However, the function of DUF506 genes in Brassica rapa (B. rapa) remains unclear. In this study, a total of 18 BrDUF506 genes were identified and randomly distributed across eight chromosomes, categorized into four subfamilies. Analyzing their promoter sequences has uncovered various stress-responsive elements, such as those for drought, methyl jasmonate (MeJA), and abscisic acid (ABA). Bra000098 and Bra017099 exhibit significantly enhanced expression in response to heat and drought stress. Protein interaction predictions indicate that Bra000098 homolog, At2g38820, is interacting with ERF012 and PUB48 and is involved in abiotic stress regulation. Furthermore, gene expression profiling has identified Bra026262 with a high expression level in flowers and significantly decreased in female sterile mutants. Protein interaction prediction further revealed that its homolog, At4g32480, interacts with MYB and AGL proteins, suggesting the potential roles in female gametophyte development. The current study enhances our understanding of the functional roles of BrDUF506s, providing significant insights that are valuable in investigating sexual reproduction and abiotic stress responses in B. rapa. [ABSTRACT FROM AUTHOR]