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This study focuses on the investigation of the mechanical properties and corrosion resistance of 430 ferritic stainless steel with an addition of 0.30% Sn， by incorporating varying amounts of Cu into the experimental steel. The results of room temperature and high temperature tensile tests reveal that Cu atoms act as solid solution strengtheners in the matrix， enhancing the tensile strength of the stainless steel. However， the formation of a significant amount of Cu-rich phase at grain boundaries leads to a decrease in the steel's plasticity. The uniform corrosion resistance of the steel initially increases and then decreases with increasing Cu content， reaching the highest effectiveness at 0.45% Cu. Similarly， Cu exhibits a comparable pattern in its resistance to intergranular corrosion in the experimental steel， achieving the best outcomes at a content of 0.98% Cu.

In this paper, the acceleration process of BaTiO3 ceramic particles under different vacuum cold spraying parameters was simulated, and the effect of process parameters on particle velocity was discussed. The results were verified using particle image velocimeter. BaTiO3 ceramic coatings were prepared using vacuum cold spraying method and their properties were tested. The simulation results showed that the particle velocity increased with the increase of gas pressure and preheating temperature. It was observed that under the same gas pressure and preheating temperature, the smaller the diameter of the particle, the more it was affected by the bow shock wave. The acceleration pattern of multiple particles was found to be similar to that of a single particle. According to the results obtained from particle image velocimetry, under the condition of and 300 K and 373 K at 0.2 MPa, the velocity of BaTiO3 particles differed from the simulation results by about 10.2% and 8.1%, respectively. Under the process parameters, as indicated by the simulation results, the continuous and dense BaTiO3 coatings with a thickness around 2 to 3 μm were fabricated by vacuum cold spraying, and the binding force was found to be 8 N. The research results indicated that the process parameters and their influence laws, obtained through numerical simulation combined with particle image velocimetry, were reliable and could be used to guide the preparation of flexible ceramic films.

CoCrMoNbTi refractory high-entropy alloy powders were prepared by mechanical alloying, and the CoCrMoNbTi high-entropy alloy coatings were successfully prepared by laser cladding technology. The influence of ball milling time on the phase composition and microstructure of the CoCrMoNbTi refractory high-entropy alloy powders and coatings were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrum (EDS) analysis. The results show that, with the increase of milling time, the diffraction peak of the pure metal phase gradually disappears, which is mainly related to the melting point of the alloying element. In addition, the powder morphology changes significantly with the extension of milling time. The powders are extruded from the original state into the flake, and the flake powders are gradually welded together to form the flat powder particles. When the milling time reaches 40 h, the powders are completely alloyed, the powder shape tends to be spherical and greatly refined, and the elements in the powders are evenly distributed, forming a stable single-phase body-centered cubic solid solution structure. The CoCrMoNbTi refractory high entropy alloy coatings prepared by laser cladding technology have the good forming quality. The coatings are mainly composed of the body-centered cubic solid solution structure and a small amount of Cr2Nb and Co2Ti compounds, forming a fine and compact dendritic structure.

Through network textual analysis, this paper explores the inheritance and development of Cao Zhi’s Luoshen Fu on pre-Qin literature, revealing its innovations in linguistic style, emotional expression and literary concepts. In-depth discussion of Cao Zhi’s Luoshen Fu on the inheritance and innovation of pre-Qin literature. The study firstly analyzes the main themes and emotional tendencies of Luoshen Fu by modeling textual themes through natural language processing techniques. In the word distribution analysis, we find that the frequency of verb and noun usage in Luoshen Fu is 221‰ and 178‰, respectively, which is significantly higher than the average level of pre-Qin literature (232‰ and 140‰). In addition, Luoshen Fu demonstrates more complex and rich emotional changes in the emotional analysis than Li Sao. By calculating the information entropy value of Luoshen Fu (10.5), compared with the average level of pre-Qin literature (9.8), it reflects its richness and innovation in vocabulary use. Luoshen Fu demonstrates remarkable innovation in language style, emotional expression, and literary concepts while demonstrating a profound ancestry in pre-Qin literature.

In the Internet era, the combination of traditional Chinese culture and the teaching of Chinese language and literature has become an important topic of education reform, and exploring its innovative mode is of great significance for the inheritance of culture and the enhancement of teaching effect. The study adopts the independent cooperation mode, builds a new cultural position based on the Internet, and adds classroom practice links to enhance the teaching effect. The teaching activities are designed based on the framework of self-study before class, interaction during class, and summarization after class. In addition, this study uses fuzzy C-mean clustering and multiple regression analysis to mathematically model educational data and deeply analyze the influencing factors of teaching quality. Teaching experiments showed that the reformed teaching model significantly improved students’ performance, and the average grade of students increased by 9.6130 points compared with the traditional teaching model. In addition, multiple regression analysis revealed that course completion, learning engagement and teaching interaction significantly affected students’ performance. The results of this study are of practical significance for promoting the innovative development of teaching Chinese language and literature.

Scrophulariae Radix (SR), the dried root of Scrophularia ningpoensis Hemsl (S. ningpoensis), has been extensively used as traditional Chinese medicine for thousands of years. However, since the mid-20th century, the traditional processing technology of S. ningpoensis has been interrupted. Therefore, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technology, together with a Global Natural Product Social Molecular Networking (GNPS) method, was applied to comprehensively analyze the characteristic changes and mutual transformation of chemical constituents in the differently processed roots of S. ningpoensis, as well as to scientifically elucidate the processing mechanism of differently processed SR. As a result, a total of 149 components were identified. Notably, with the help of the GNPS data platform and MS2 fragment ions, the possible structures of four new compounds (47, 48, 50, and 73) were deduced in differently processed SR samples, in which 47, 48, and 50 are iridoid glycosides, and 73 is a phenylpropanoid glycoside. Five cyclopeptides (78, 86, 97, 99, and 104) derived from leucine (isoleucine) were identified in SR for the first time. The heatmaps analysis results indicated that leucine or isoleucine may be converted to cyclopeptides under the prolonged high-temperature conditions. Moreover, it is found that short-time steaming can effectively prevent the degradation of glycosides by inactivating enzymes. This study provides a new and efficient technical strategy for systematically identifying the chemical components, rapidly discovering the components, and preliminarily clarifying the processing mechanism of S. ningpoensis, as well as also providing a scientific basis for the improvement of the quality standards and field processing of S. ningpoensis. [ABSTRACT FROM AUTHOR]

Introduction: Scrophulariae Radix (SR) has been extensively used in traditional Chinese medicine (TCM) for thousands of years. However, the processing methods and production areas of Scrophularia ningpoensis have undergone notable historic changes. Thus, their effects on the bioactive constituents of SR still need to be studied further. Objectives: This study aimed to establish an objective and comprehensive method to identify the correlation of bioactive constituents of SR with variety, place of origin and processing method for evaluating their qualities. Methodology: An accurate and rapid high‐performance liquid chromatography‐diode array detector (HPLC‐DAD) method for the simultaneous determination of 11 marker components (aucubin, harpagide, 6‐O‐methyl‐catalpol, harpagoside, verbascoside, isoverbascoside, angoroside C, cinnamic acid, l‐tyrosine, l‐phenylalanine, and l‐tryptophan) was established to evaluate the quality of SR for the first time. In addition, the effects of different production areas and processed methods on the target compounds were studied by analysing 66 batches of SR samples with chemometrics methods, including similarity evaluation of chromatographic fingerprints of TCM, principal component analysis (PCA), and partial least squares‐discriminant analysis (PLS‐DA). Results: Compared with "sweating", short‐term "steaming" and "slice‐drying" could largely preserve the bioactive constituents of SR. When using the model established through PLS‐DA, five components were identified as the most significant variables for discrimination. Furthermore, the score plots of PCA and the similarity evaluation revealed that variety had a more notable influence on the quality of SR than the place of origin. Conclusion: An objective approach of HPLC fingerprint coupled with chemometrics analysis and quantitative assessment could be applied to discriminate different processed SR and evaluate the qualities of SR rapidly. An accurate and comprehensive HPLC‐DAD method for the simultaneous determination of 11 marker components was established to identify the correlation of bioactive constituents of SR with variety, place of origin, and processing methods. In addition, chemometrics methods, including similarity evaluation of chromatographic fingerprints of TCM, PCA, and PLS‐DA, were used to analyze 66 batches of SR samples based on the target compounds. The above work could be applied to discriminate different processed SR and evaluate the qualities of SR rapidly. [ABSTRACT FROM AUTHOR]

Neurobrucellosis has been reported to cause lesions in a number of different locations in the central nervous system. Histologically or radiologically, these lesions were consistent with an infection. In response to parents who believed their child's brain tumor, histologically typical of medulloblastoma, was in reality neurobrucellosis, formalin-fixed paraffin-embedded tumor tissue from the medulloblastoma was sectioned, DNA extracted, and tested by polymerase chain reaction (PCR). Specific primer/probe sets, designed in our laboratory to target Brucella species, B. melitensis, B. abortus and B. suis, and designated OMP31, B-m, B-a and B-s, respectively, were used in TaqMan real-time PCR to amplify those gene targets in two separate blocks of the child's tumor. Sections from two blocks were positive only for Brucella species. Although the patient grew up in a European country known to harbor brucella in foods, such as unpasturized milk and cheese, the patient was seronegative for B. mellitensis, B. suis, and B. abortus. In an effort to test whether a relationship existed between the presence of brucella and medulloblastoma, 20 medulloblastomas were retrieved from the tissue repository of the AFIP. The above four primer/probe sets were again used to amplify brucella DNA. Five of 20 tumors (25%) contained Brucella species DNA by the OMP31 primer/probe set. None of the 20 medulloblastomas had specific sequences for B. mellitensis, B. suis, or B. abortus. Is chronic brucellosis similar to other infectious agents such as helicobacter that is associated with tumor formation?