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Objective: The purpose of this study was to optimize the roasting process for Xinjiang Nang pit-roasted lamb meat and explore the effects of variable-temperature roasting on the roasting loss percentage, color, tenderness, and heterocyclic aromatic amine (HAA) and polycyclic aromatic hydrocarbon (PAH) contents of roasted lamb meat. Methods: The three-stage variable-temperature roasting process involving high temperature (T1), roasting time (t1), medium temperature (T2), roasting time (t2), low temperature (T3), and roasting time (t3) was optimized using an L27 (36) orthogonal array design and fuzzy mathematics comprehensive evaluation method. The differences in the contents of HAAs and PAHs in lamb meat roasted at variable temperature (CK), high temperature (HT) and low temperature (LT) were analyzed. Results: The decreasing order of the influence of variable-temperature roasting parameters on the sensory evaluation of roasted lamb meat was as follows: T1 > t2 > T2 > t1 > t3 > T3. The optimal roasting parameters were T1 = 300 ℃, t1 = 4 min, T2 = 220 ℃, t2 = 6 min, T3 = 100 ℃, t3 = 7 min, and the sensory score of lamb meat roasted under these conditions was 3.408 out of 4 points. There was a significant positive correlation between roasting loss percentage and T2 (r = 0.50), between shearing force and T1 (r = 0.47), between internal L* value and t1 (r = 0.57), between surface a* value and sensory evaluation (r = 0.64), and between surface b* value and roasting loss percentage (r = 0.40). The total content of HAAs in roasted lamb meat was in decreasing order of HT > LT > CK. The highest roasting temperature in the CK group was the same as that in the HT group, but the total content of HAAs in the CK group was significantly lower than that in the HT group (P 0.05). Principal component analysis of the total amounts of HAAs in the HT, LT and CK groups showed that the substances with the highest contribution rate to the first principal component (PC1) were 2-amino-3,4-dimethylimidazo[4,5-ƒ]quinolone (MeIQ), 2-amino-3-methylimidazo[4,5-ƒ]quinoxaline (IQx) and 2-amino-3,7,8-trimethylimidazo[4,5-ƒ]quinoxaline (7,8-DiMeIQx), respectively. The total content of PAHs in the HT group was (427.45 ± 27.84) ng/g, which was significantly higher than that in the LT and CK groups (P < 0.05). The substances with the largest contribution rate to PC1 and the second principal component (PC2) were phenanthrene (Phe) and benz[a]anthracene (BaA) for the LT group, respectively, and the substance with the largest contribution rate to PC1 were BaA for the CK group. Conclusion: High-temperature roasting temperature is the key factor affecting the eating quality of lamb meat roasted at variable temperature, and variable-temperature roasting effectively reduces the total content of HAAs and PAHs in roasted lamb meat.

【Objective】 Poyang Lake is one of the largest lakes in southern China but has experienced pollution due to agricultural activities. This paper aims to analyze the changes in nitrogen (N) and phosphorus (P) loss via surface runoff from cropped lands under different planting practices in the basin. 【Method】 For each crop, we compared three planting practices: upland farming, paddy farming, and alternate upland and paddy farming. The experiment lasted two years, during which we measured precipitation, surface runoff and changes in N and P in the surface runoff. 【Result】 The peak rainfalls occurred in June and July, aligning with the highest flow rates under all three planting practices. In the three planting practices, cabbage and early rice had the highest crop runoff, while pakchoi and late rice had the least, with rape and middle rice between. The runoff coefficient was the largest for cabbage and least for late rice, consistent with the change in rainfall intensity during growth seasons of the crops. The crop runoff of the three planting practices was ranked in the order of upland farming>alternate paddy and upland farming>paddy farming. Compared with paddy farming, upland farming and alternate paddy and upland farming increased the crop runoff by 42.28% and 20.84%, respectively. In all three planting practices, nitrogen and phosphorus loss via the surface runoff occurred from May to July. Water spinach under upland farming lost most total N, total P, and nitrate, while middle rice under alternate paddy and upland farming lost most ammonium nitrogen. The losses of total N, total P, and nitrate N via surface runoff from the three planting practices were consistent with the variations in crop runoff. Nitrogen loss from upland farming is through nitrate leaching, while N loss from the rice fields was mainly ammonium. 【Conclusion】 Upland farming resulted in the highest surface runoff, and N and P losses. These findings have important implications for improving planting practices to improve fertilizer use efficiency and mitigate N and P losses in the Poyang Lake basin.

Most structural faults in metal parts can be attributed to fatigue crack propagation. The analysis and prognostics of fatigue crack propagation play essential roles in the health management of mechanical systems. Due to the impacts of different uncertainty factors, the crack propagation process exhibits significant randomness, which causes difficulties in fatigue life prediction. To improve prognostic accuracy, a physics-based Tweedie exponential dispersion process (TEDP) model is proposed via integrating Paris Law and the stochastic process. This TEDP model can capture both the crack growth mechanism and uncertainty. Compared with other existing models, the TEDP taking Wiener process, Gamma process, and inverse process as special cases is more general and flexible in modeling complex degradation paths. The probability density function of the model is derived based on saddle-joint approximation. The unknown parameters are calculated via maximum likelihood estimation. Then, the analytic expressions of the distributions of lifetime and product reliability are presented. Significant findings include that the proposed TEDP model substantially enhances predictive accuracy in lifetime estimations of mechanical systems under varying operational conditions, as demonstrated in a practical case study on fatigue crack data. This model not only provides highly accurate lifetime predictions, but also offers deep insights into the reliability assessments of mechanically stressed components. [ABSTRACT FROM AUTHOR]

The utilization of drone technology thrives in diverse domains, including aviation, military operations, and logistics. The pervasive adoption of this technology aims to enhance efficiency while mitigating hazards and expenditures. In complex contexts, the governing parameters of uncrewed aerial vehicles (UAV) require real-time adjustments for flight safety and efficacy. To improve the attitude estimation accuracy, this article introduces a ATT-Bi-LSTM framework for optimizing UAVs through adaptive parameter control, which integrates the state information gleaned from communication signals. The ATT-Bi-LSTM achieves data feature extraction by means of a two-layer Bidirectional Long Short-Term Memory (BI-LSTM) at its inception to enhance the feature. Subsequently, it harnesses the attention mechanism to amplify the LSTM network's output, thereby enabling the optimal control of UAV positioning. During the empirical phase, we employ optical system data for the comparative validation of the model. The outcomes underscore the commendable performance of the proposed framework in this study, particularly with regard to the three pivotal position indicators: yaw, pitch, and roll. In the comparison of indicators such as RMSR and MAE, the proposed model has the lowest error, which provides algorithm support and important reference for future UAV optimization control research. [ABSTRACT FROM AUTHOR]

A partitionable adaptive multilayer diffractive optical neural network is constructed to address setup issues in multilayer diffractive optical neural network systems and the difficulty of flexibly changing the number of layers and input data size. When the diffractive devices are partitioned properly, a multilayer diffractive optical neural network can be constructed quickly and flexibly without readjusting the optical path, and the number of optical devices, which increases linearly with the number of network layers, can be avoided while preventing the energy loss during propagation where the beam energy decays exponentially with the number of layers. This architecture can be extended to construct distinct optical neural networks for different diffraction devices in various spectral bands. The accuracy values of 89.1% and 81.0% are experimentally evaluated for MNIST database and MNIST fashion database and show that the classification performance of the proposed optical neural network reaches state-of-the-art levels. [ABSTRACT FROM AUTHOR]

Background: The volume of epicardial adipose tissue (EAT) is associated with an increased incidence of cardiovascular disease (CVD); however, only a few studies have examined its effect on the myocardial function of endurance in athletes. The association between the EAT and the variation of myocardial function is still unclear in amateur marathoners. Consequently, by using some sedentary individuals as the control, this study aims to evaluate the correlation between the EAT volume and the myocardial strain in the left and right ventricles of Chinese amateur marathoners by cardiac magnetic resonance (CMR). Methods: A total of 30 amateur marathoners were included as the exercise group and 20 sedentary people as a control group. All participants received the cardiac magnetic resonance (CMR) to measure the left and right ventricular end-diastolic volume, end-systolic volume and volume index, stroke volume and index, cardiac output index, ejection fraction and myocardial mass, the EAT volume, global radial, circumferential, and longi-tudinal strains, and the strain rates of left and right ventricular myocardium. Results: There was a significant difference in the EAT volume (EATV) index between the exercise group and the control group (26.82±11.76ml/m2 vs 37.82±17.15ml/m2, P = 0.01). Results from the multivariate linear regression analysis showed that BMI (standardized β = 0.458; P < 0.001) had an independent positive correlation with the EATV index. The EATV index was negatively correlated with the left ventricular global radial strain (GRS) (r = -0.505; P = 0.004) in the exercise group, while it is negatively correlated with right ventricular GRS (r = -0.492; P = 0.027) and positively correlated with global longitudinal strain (GLS) (r = 0.601; P = 0.005) in the control group. In the exercise group, the multivariate linear regression analysis showed that the EATV index (standardized β = -0.429; P = 0.021) was an independent determinant of the left ventricular GRS, and being a male (standardized β = 0.396; P = 0.029) was an independent determinant of the right ventricular GLS. Conclusion: The EATV index is independently correlated with the left ventricular GRS in the amateur Chinese marathoners, also, the amateur marathon reduces the EATV index and increases the left ventricular myocardial mass, which consequently reduces the adverse effects on myocardial function. [ABSTRACT FROM AUTHOR]

Tip growth is an extreme form of polarized cell expansion that occurs in all eukaryotic kingdoms to generate highly elongated tubular cells with specialized functions, including fungal hyphae, animal neurons, plant pollen tubes, and root hairs (RHs). RHs are tubular structures that protrude from the root epidermis to facilitate water and nutrient uptake, microbial interactions, and plant anchorage. RH tip growth requires polarized vesicle targeting and active exocytosis at apical growth sites. However, how apical exocytosis is spatially and temporally controlled during tip growth remains elusive. Here, we report that the Qa-Soluble N -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) SYP121 acts as an effector of Rho of Plants 2 (ROP2), mediating the regulation of RH tip growth. We show that active ROP2 promotes SYP121 targeting to the apical plasma membrane. Moreover, ROP2 directly interacts with SYP121 and promotes the interaction between SYP121 and the R-SNARE VAMP722 to form a SNARE complex, probably by facilitating the release of the Sec1/Munc18 protein SEC11, which suppresses the function of SYP121. Thus, the ROP2-SYP121 pathway facilitates exocytic trafficking during RH tip growth. Our study uncovers a direct link between an ROP GTPase and vesicular trafficking and a new mechanism for the control of apical exocytosis, whereby ROP GTPase signaling spatially regulates SNARE complex assembly and the polar distribution of a Q-SNARE. Root hair tip growth requires polarized vesicle targeting and active exocytosis at apical growth site, but how it is spatially and temporally controlled remains elusive. This study demonstrates that ROP2 directly regulates the polar localization of SYP121 and its interaction with VAMP722 for SNARE complex assembly, establishing a tight link between ROP signaling and apical exocytosis during root hair tip growth. [ABSTRACT FROM AUTHOR]

In this study, the digestion of pectic polysaccharide from Brassica rapa L. (BRP) in vitro and its effect on the intestinal microbiota in cyclophosphamide (Cy)‐treated mice were investigated. As a result, the molecular weight (Mw) of BRP was significantly decreased after simulated gastrointestinal digestion, and content of reducing sugars (CR) was significantly increased (P < 0.05), implying that BRP was gradually degraded under gastrointestinal digestion conditions in vitro. In vivo, both 50 or 200 mg kg−1·BW/d of BRP significantly improved SCFAs concentrations that decreased by Cy treatment (P < 0.05). Meanwhile, BRP enriched the alpha‐diversity of intestinal microbiota and altered the microbial composition with an increase of Lactobacillus and a decrease of Clostridium, Ruminococcus, Oscillospira (P < 0.05). Besides, BRP intervention was conducive to the recovery of mouse body weight, thymus and spleen indices, and contributed to improve the intestinal barrier. [ABSTRACT FROM AUTHOR]

Abstract The effects of the gas phase surface discharge plasma system with a spray reactor on yeast in 12, 36, and 60°Brix apple juice were evaluated. Results indicated that the number of Zygosaccharomyces rouxii LB cells in 0.5 L of 12°Brix apple juice was reduced by 5.60 log 10 after discharge plasma treatment for 30 min. When the soluble solids content increased from 12 to 60°Brix, yeast inactivation was decreased by 2.55 log 10. After treatment, the pH level of the apple juice only slightly increased, and the titratable acidity and concentration of reducing sugars remained unchanged. The total color differences between the plasma-treated and untreated samples in 12, 36, and 60°Brix apple juice were 9.53, 7.97, and 3.86. Meanwhile, the concentrations of alcohols, esters, aldehydes, and ketones—the main components of volatile compounds showed no significant change (p < 0.05). Industrial relevance Inactivation of microorganisms using nonthermal plasma technology can reduce food costs and minimize changes in food products and is therefore an alternative to heat-based technology. The proposed research showed that the gas phase surface discharge plasma treatment with a spray reactor can effectively reduce Zygosaccharomyces rouxii in apple juice. In addition, the effect of plasma treatment on the color and volatile compounds of the apple juice were determined. This study provided a technical support for the application of plasma technology in apple juice processing. Highlights • Yeast cells were reduced by 3.05–5.60 log 10 after plasma treatment for 30 min. • Increased soluble solids content negatively affected yeast inactivation. • Plasma treatment did not affect titratable acidity and reducing sugar content. • The total color differences in samples were 3.86–9.53 after plasma treatment. • Plasma treatment did not change in volatile compounds, compared with the control. [ABSTRACT FROM AUTHOR]

Methyl jasmonate (MeJA) plays important roles on growth, gene expression and metabolite accumulation in plants. In this study, the physiological and biochemical characteristics, transcriptome and metabolome profiles of Isatis indigotica Fort., responded to MeJA were explored. Under the treatment, the contents of dry matter, chlorophyll and carotenoids increased significantly, while the water content did not. And the contents of soluble protein, flavonoid and lignin were also raised significantly, but the soluble sugar decreased. Besides, the enzyme activities of phenylalanine ammonia lyase (PAL), lipoxygenase (LOX), polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) increased, showing certain resistance characteristics of this plant. Based on RNA-seq, 31,769 unigenes were functionally annotated, and 2725 differential expressed genes (DEGs) identified. Among them, 57 DEGs covered most of the catalytic steps in general biosynthesis pathways of jasmonic acid, glucosinolates and phenylpropanoid. Referring to the metabolomics analysis, 175 significant differential metabolites were detected by GC-MS, combined with LC-MS method. Moreover, 53 differential metabolites were identified by the multivariate statistical analysis, mainly enriched in 37 different metabolic pathways, with most differential metabolites found in phenylalanine metabolism pathway. The results provided the comprehensive analysis on growth, transcriptome and metabolite profiles responded to MeJA, and gave new insights into revealing and enriching the functions of MeJA, contributing to explore the key genes and their functions on growth and metabolite accumulation and regulation process in I. indigotica. • MeJA could improve the seedling growth and enhance the resistance of I. indigotica. • A total of 2725 genes differentially expressed in response to MeJA. • 175 metabolites differentially changed in response to MeJA. [ABSTRACT FROM AUTHOR]

Atmospheric cold plasma is a powerful and profitable microbial decontamination technology in the food industry. The microbial load and food matrix have a great influence on the plasma inactivation effect. This study aimed to quantify the effects of initial cell concentration and soluble solids on the inactivation of yeast in apple juice by gas-phase surface discharge plasma. A computer simulation model was developed to predict the inactivation process using commercial finite element software, COMSOL Multiphysics, and the model was verified by experiments. Studies have shown that the inactivation of yeast was affected by the initial cell concentration and soluble solids. These effects were quantified by fitting equations and used as model inputs. The simulation model predicted the D-value of plasma inactivation of yeast under different discharge voltages and apple juice volume, which was verified in experiments. Therefore, the established model can be used for plasma development to predict how the food matrix affects the inactivation process, thereby providing useful and practical tools for amplifying the commercial application of plasma. • A surface discharge voltage plasma deactivation model was developed and verified. • Model correlated the cell concentration and soluble solids with inactivation rates. • The influence of discharge voltage and process capacity was predicted in the model. [ABSTRACT FROM AUTHOR]

Auxin is one of the most critical hormones in plants. YUCCA (Tryptophan aminotransferase of Arabidopsis (TAA)/YUCCA) enzymes catalyze the key rate-limiting step of the tryptophan-dependent auxin biosynthesis pathway, from IPA (Indole-3-pyruvateacid) to IAA (Indole-3-acetic acid). Here, 13 YUCCA family genes were identified from Isatis indigotica, which were divided into four categories, distributing randomly on chromosomes (2n = 14). The typical and conservative motifs, including the flavin adenine dinucleotide (FAD)-binding motif and flavin-containing monooxygenases (FMO)-identifying sequence, existed in the gene structures. IiYUCCA genes were expressed differently in different organs (roots, stems, leaves, buds, flowers, and siliques) and developmental periods (7, 21, 60, and 150 days after germination). Taking IiYUCCA6-1 as an example, the YUCCA genes functions were discussed. The results showed that IiYUCCA6-1 was sensitive to PEG (polyethylene glycol), cold, wounding, and NaCl treatments. The over-expressed tobacco plants exhibited high auxin performances, and some early auxin response genes (NbIAA8, NbIAA16, NbGH3.1, and NbGH3.6) were upregulated with increased IAA content. In the dark, the contents of total chlorophyll and hydrogen peroxide in the transgenic lines were significantly lower than in the control group, with NbSAG12 downregulated and some delayed leaf senescence characteristics, which delayed the senescence process to a certain extent. The findings provide comprehensive insight into the phylogenetic relationships, chromosomal distributions, and expression patterns and functions of the YUCCA gene family in I. indigotica. [ABSTRACT FROM AUTHOR]

Zygosaccharomyces rouxii is an osmotolerant yeast responsible for the quality degradation of apple juices. Cold plasma is a promising method for microbial inactivation. The primary purpose of this work was to study the influence of electrical discharge plasma treatment on hypertonic yeast inactivation in apple juice. The gas-phase surface discharge was triggered along a quartz tube in an electrical discharge plasma system, and then highly reactive species were bubbled into commercial apple juice artificially inoculated with yeast. The results showed that the yeast in the apple juice reached a 5.6 log 10 reduction after the plasma exposure for 30 min at a 21 kV discharge voltage. Scanning electron microscopy showed that cell structure was damaged during plasma treatment. Plasma treatment caused a slight increase in pH, while the total soluble solids, titration acidity, and reducing sugar did not significantly change. After treatment, the apple juice brightness and hue values increased, the colour became yellower and lighter, and the main components of volatile compounds did not change significantly (p < 0.05). Plasma treatment can inactivate hypertonic yeast while maintaining the physicochemical properties of apple juice, including the retention of the volatile compounds in apple juice. • Yeast content in apple juice can be inactivated by electrical discharge plasma. • A 5.60-log reduction in yeast can be achieved by an exposure time of 30 min. • Titratable acidity and reducing sugar content did not change upon plasma treatment. • The total colour differences in samples were 2.96–9.77 after plasma treatment. • Electrical discharge plasma treatment can retain volatile compounds in apple juice. [ABSTRACT FROM AUTHOR]

Background The human uterus is traditionally believed to be sterile, while the vaginal microbiota plays an important role in fending off pathogens. Emerging evidence demonstrates the presence of bacteria beyond the vagina. However, a microbiome-wide metagenomic analysis characterizing the diverse microbial communities has been lacking. Results We performed shotgun-sequencing of 52 samples from the cervical canal and the peritoneal fluid of Chinese women of reproductive age using the Illumina platform. Direct annotation of sequencing reads identified the taxonomy of bacteria, archaea, fungi and viruses, confirming and extending the results from our previous study. We replicated our previous findings in another 24 samples from the vagina, the cervical canal, the uterus and the peritoneal fluid using the BGISEQ-500 platform revealing that microorganisms in the samples from the same individuals were largely shared in the entire reproductive tract. Human sequences made up more than 99% of the 20GB raw data. After filtering, vaginal microorganisms were well covered in the generated reproductive tract gene catalogue, while the more diverse upper reproductive tract microbiota would require greater depth of sequencing and more samples to meet the full coverage scale. Conclusions We provide novel detailed data on the microbial composition of a largely unchartered body site, the female reproductive tract. Our results indicated the presence of an intra-individual continuum of microorganisms that gradually changed from the vagina to the peritoneal fluid. This study also provides a framework for understanding the implications of the composition and functional potential of the distinct microbial ecosystems of the female reproductive tract in relation to health and disease. [ABSTRACT FROM AUTHOR]

Abstract: ZnSe quantum dots (QDs) were synthesized by using a novel oleic acid-controlled hydrothermal route. The as-synthesized QDs were easily dispersed in nonpolar solvents to form highly stable homogenous solutions, on the basis of which their optical properties were systematically investigated. It was found that the QDs had multiple optical properties of both obvious optical nonlinearity with a frequency-doubled Nd:YAG laser (532 nm) used as inducing beam and a strong photoluminescence emission at ca. 458 nm, suggesting that they have potential applications in complex functional optical devices. [Copyright &y& Elsevier]

• Richness of the lower respiratory tract microbiome is diminished in patients with lung cancer. • Bradyrhizobium japonicum was only discovered in patients with lung cancer. • Acidovorax was a lineage found only in patients with pulmonary diseases. • A model based on age, pack year of smoking and 11 kinds of microbiota was created and validated. Current evidence suggests that microorganisms are associated with neoplastic diseases; however, the role of the airway microbiome in lung cancer remains unknown. To investigate the taxonomic profiles of the lower respiratory tract (LRT) microbiome in patients with lung cancer. BALF samples were collected in a discovery set comprising 150 individuals, including 91 patients with lung cancer, 29 patients with nonmalignant pulmonary diseases and 30 healthy subjects, and an independent validation set including 85 participants. The samples were assessed by metagenomics analysis. Random forest regression analysis was performed to select a diagnostic panel. In the discovery set, richness was reduced in lung cancer patients compared with that in healthy subjects, and the microbiome of patients with nonmalignant diseases resembled that of patients with lung cancer. Interestingly, Bradyrhizobium japonicum was only found in patients with lung cancer, whereas Acidovorax was found in patients with cancer and nonmalignant pulmonary diseases. A microbiota-related diagnostic model consisting of age, pack year of smoking and eleven types of bacteria was built, and the area under the curve (AUC) for discriminating the patients with cancer was 0.882 (95%CI: 0.807-0.957) in the training set and 0.796 (95%CI: 0.673-0.920) in the independent validation set. Our study demonstrates that the LRT microbiome richness is diminished in lung cancer patients compared with that in healthy subjects and that microbiota-specific biomarkers may be useful for diagnosing patients for whom lung biopsy is not feasible. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports on the thermal-induced performance of hexagonal metastable In2O3 nanocrystals involving in phase transition and assembly, with particular emphasis on the assembly for the preparation of functional materials. For In2O3 nanocrystals, the metastable phase was found to be thermally unstable and transform to cubic phase when temperature was higher than 600°C, accompanied by assembly as well as evolution of optical properties, but the two polymorphs coexisted at the temperature ranging from 600 to 900°C, during which the content of product phase and crystal size gradually increased upon increasing temperature. The assembly of In2O3 nanocrystals can be developed to fabricate In2O3 functional materials, such as various ceramic materials, or even desired nano- or micro-structures, by using metastable In2O3 nanocrystals as precursors or building blocks. The electrical resistivity of In2O3 conductive film fabricated by a hot-pressing route was as low as 3.72×10−3 Ωcm, close to that of In2O3 single crystal, which is important for In2O3 that is always used as conductive materials. The findings should be of importance for both the wide applications of In2O3 in optical and electronic devices and theoretical investigations on crystal structures. [ABSTRACT FROM AUTHOR]

In this paper, the interface properties and interfacial interaction were calculated by the first principle method, and the growth of γ-Fe boundary was inhibited by La 2 O 3 so as to refine the austenite grain was also analyzed. The calculated results show that the two-dimensional lattice mismatch between γ-Fe(110) plane and La 2 O 3 (001) plane is 8.7%. Therefore, the nucleation interface between γ-Fe and La 2 O 3 is most likely γ-Fe(110)/La 2 O 3 (001). Meanwhile, there are three kinds of interface models, which are Fe–La-OT, Fe–La-OM and Fe–La-Bridge, respectively. The interface adhesion work of Fe–La-OT interface is smallest, which is −0.10 J/m2, while, that of Fe–La-OM interface is largest, which is −0.02 J/m2. The ideal interface adhesion work of the three interfaces is negative, which indicates that they cannot be existed stably. The three kinds of interfacial chemical bonds are composed of ionic bonds and metallic bonds. The chemical bond polarity of Fe–La-OT interface is the strongest, and the metallic property of Fe–La-OM interface and Fe–La-Bridge interface is stronger than that of Fe–La-OT one. In addition, most interfacial interaction forces of the three interface models are repulsive, which indicates that La 2 O 3 has a good inhibitory effect on the growth interface of γ-Fe. Therefore, La 2 O 3 can inhibit the growth of γ-Fe boundaries so as to refine the austenite grains. Image 1 • Work of adhesion and interfacial energy ofγ-Fe(110)/La 2 O 3 (001) interfaces were calculated. • Interfacial electronic structures between γ-Fe and La 2 O 3 were analyzed. • Interfacial bond characteristics were revealed by electron localization function and interface DOS. • The mechanism that the La 2 O 3 refine the austenite grain was analyzed. [ABSTRACT FROM AUTHOR]

The first principles method was used to calculate the interface stability, interfacial electronic structure and bond characteristics of γ-Fe/CeO 2 heterogeneous nucleation interface. Meanwhile, The formation mechanism of (100)_γ-Fe/(111)_CeO 2 heterogeneous nucleation interface was also revealed. The calculation results show that the two dimensional lattice mismatch between (100)_γ-Fe and (111)_CeO 2 is 4.9%, which indicates that (100)_γ-Fe and (111)_CeO 2 satisfy the crystallographic condition for the formation of effective heterogeneous nucleation interface. There are two kinds of interface models, named as O1-Fe and O2-Fe. The stability of O1-Fe interface is the best and its interfacial energy is the lowest, which is 3.07 J/m2. The ideal interfacial adhesive strength of O2-Fe interface is the largest, which is 10.98 J/m2. The bond characteristics of the two interfaces are both mixtures of covalent bonds and ionic bonds. It reveals that (100)_γ-Fe and (111)_CeO 2 can form effective heterogeneous nucleation interfaces and O1-Fe interface model forms preferably during the heterogeneous nucleation beginning process. When the formation conditions meet the requirement for both interface structures, the adhesive strength of the O2-Fe interface is higher. Therefore, CeO 2 can act as effective heterogeneous nucleation substrate of γ-Fe to refine the austenite grains. Image 1 • Two dimensional lattice mismatch between (100)_γ-Fe/(111)_CeO 2 is 4.9%. • O1-Fe interface has the best stability and O2-Fe interface has the largest ideal bonding strength. • Interfacial bond characteristics are mixture of covalent bonds and ionic ones. • (100)_γ-Fe/(111)_CeO 2 heterogeneous nucleation interface formed preferably as O1-Fe type. [ABSTRACT FROM AUTHOR]