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Atmospheric plasma-sprayed FeCoCrNiMo0.2 high-entropy alloy (HEA) coatings were annealed under various temperatures. The effects of annealing temperature on the microstructure and corrosion resistance of the coatings were investigated. The results showed that the grain size of the coating was significantly refined after annealing. With the increase of annealing temperature, the streamlined fluctuation of the interlayer structure of the coating layer gradually increased. Mo atoms with lower solid solubility precipitated from the HEA lattice. At the same time, the porosity first decreased and then increased. The lowest porosity of the coating was found at 1000°C. When the annealing temperature was increased from 0 to 1000°C, the open circuit point potential of the coatings was positively shifted from − 0.49844 to − 0.43651, Ecorr was positively shifted from − 0.73 V to − 0.57 V, and the Icorr was decreased from 6.992 × 10−6 A/cm2 to 2.1747 × 10−6 A/cm2. Reduced porosity, an increase in oxide streamline fluctuations, and the precipitation of Mo atoms to form a stable cured film were the main reasons for the improved corrosion resistance of the coatings. Excessively high annealing temperatures can lead to cracks in the coating under stress. Coatings annealed at 1000°C had the best corrosion resistance. [ABSTRACT FROM AUTHOR]

Landslide risk management contributes to the sustainable development of the region. Understanding the spatial controls on the distribution of landslides triggered by earthquakes (EqTLs) is difficult in terms of the prediction and risk assessment of EqTLs. In this study, landslides are regarded as a spatial point pattern to test the controls on the spatial distribution of landslides and model the landslide density prediction. Taking more than 190,000 landslides triggered by the 2008 Wenchuan Ms 8.0 earthquake (WcEqTLs) as the research object, the relative density estimation, Kolmogorov–Smirnov testing based on cumulative distribution, receiver operating characteristic curve (ROC) analysis, and Poisson density modeling are comprehensively applied to quantitatively determine and discuss the different control effects of seven factors representing earthquakes, geology, and topography. The distance to the surface ruptures (dSR) and the distance to the epicenter (dEp) show significant and strong control effects, which are far stronger than the other five factors. Using only the dSR, dEp, engineering geological rock group (Eg), and the range, a particularly effective Poisson model of landslide density is constructed, whose area under the ROC (AUC) reaches 0.9244 and whose very high-density (VHD) zones can contain 50% of landslides and only comprise 3.9% of the study areas. This research not only deepens our understanding of the spatial distribution of WcEqTLs but also provides new technical methods for such investigation and analysis. [ABSTRACT FROM AUTHOR]

The formation of Quaternary glaciers represented a pivotal event in the climatic and geological history of the Tibetan Plateau. However, due to the scarcity of direct evidence for low-latitude glaciation, the timing and extent of late Quaternary glaciation on the Tibetan Plateau remain controversial. This study focuses on the Liangwang Mountains, which are located in the southeastern part of the Tibetan Plateau and has a maximum elevation of 2820 m, as the subject of investigation. Through a comprehensive application of glacial landform analysis, scanning electron microscopy (SEM)-based micromorphology analysis of quartz sand, and spore-pollen data analysis, we uncovered evident signs of glacial activity in this region during the Quaternary period. Our research identified typical glacial landforms such as cirques, U-shaped valleys, fluted moraines, and terminal moraines. Additionally, spore-pollen analysis revealed a high frequency of fir pollen, indicating cold climatic conditions during that time. Furthermore, the micromorphology analysis of quartz sand further corroborated the glacial origin of these deposits. Based on these combined findings, our study confirms that the Liangwang Mountains experienced glaciation during the Quaternary period, making them glacial relics at the lowest latitude currently known in mainland China. This discovery provides a valuable reference for understanding the paleoclimate and glacial history of the Tibetan Plateau and its surrounding regions. [ABSTRACT FROM AUTHOR]

Nanhong agate has attracted public attention as the most distinctive gemstone in China. Owing to the limited data on Nanhong agates from a new production area in northeastern Yunnan, this paper presents the first data from gemological studies on these agates. Complex investigations using Fourier-transform infrared (FTIR) spectrometry, ultraviolet–visible (UV–VIS) luminescence spectrometry, Raman spectroscopy, polarizing microscopy, scanning electron microscopy (SEM), electron microprobe (EPMA), and laser ablation–inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses were carried out to obtain basic data concerning the gemological properties, microstructure, and spectroscopic and geochemical characteristics of this interesting material. The results illustrate that Nanhong agates from northeastern Yunnan are mainly composed of α-quartz and also contain certain amounts of moganite, illite, goethite, and hematite. The typical red (yellow) and white appearance can be attributed to the microstructure of the agates, the contents of Fe and Al impurities, and trace elements. The Raman spectra, microstructure, and chemical composition of the unique "yellow-skinned" agates from northeastern Yunnan are significantly different from those of other types of Nanhong agate. This work lays a foundation for the future identification and research of this type of Nanhong agate. [ABSTRACT FROM AUTHOR]

Atmospheric plasma spraying (APS) is one of the most efficient processes for the preparation of yttrium oxide (Y2O3) ceramic coatings. Changing the spraying process parameters can significantly improve the microstructure and enhance the coating properties. In this study, the combination of plasma-spraying process parameters (current, spraying distance, and argon (Ar) flow) was varied by Response Surface Methodology (RSM) with the help of Minitab 19 software. Applied to the design of experiments, improvement of errors, and prediction of microstructure property results, the optimization and validation of experimental parameters for attaining the desired microstructure of Y2O3 coatings, especially porosity, was achieved. Process parameters were optimized by RSM: current 613.64 A, Ar flow rate 46.92 L/min, spray distance 15.38 cm, and optimum porosity 1.8% after optimization. Electrochemical corrosion experiments and breakdown voltage experiments revealed that the corrosion resistance and dielectric properties increased significantly as the porosity of the coatings decreased. Therefore, by optimizing the plasma-spraying process parameters, the porosity of the coatings can be significantly reduced and the corrosion resistance and dielectric properties of Y2O3 coatings can be effectively improved. [ABSTRACT FROM AUTHOR]

The aim of this paper is to develop some aggregation operators for multiple-attribute group decision making (MAGDM) with hesitant fuzzy linguistic information. First, the relationship between uncertain linguistic variable and hesitant fuzzy linguistic term set (HFLTS) is discussed. Some operations and aggregation operators for HFLTSs are developed. Second, based on the hesitant fuzzy linguistic weighted arithmetic averaging operator and the hesitant fuzzy linguistic hybrid averaging operator, an approach to MAGDM problem with hesitant fuzzy linguistic information is proposed. Finally, a practical application of the developed approach to supplier selection in a supply chain and a comparative analysis with other methods are presented.

We examined the feasibility of applying soaking root fertilizer to Eucalyptus urograndis seedlings by dipping the roots, and the effectiveness of the method for improving the overall growth quality of the seedlings by affecting root growth. The seedlings of E. urograndis in the Southern National Forest Seedling Demonstration Base in China were dipped with seven kinds of soaking root fertilizer formulas, while another group of clear water was set as a control. We regularly investigated the relationship between root traits and other seedling traits, and the formulas conducive to the high-quality growth of seedlings in one month and two months were screened by principal component analysis (PCA). The feasibility of applying soaking root fertilizer by dipping the roots was analyzed by comparing the difference between the formula and the control. The F2 formula had the best promoting effect on the growth and biomass of seedlings and the highest ground diameter within one month. The biomass, cumulative height growth, and average crown width were also the highest in the two months, but the decreasing growth height in F2 was also obvious, along with reduced photosynthesis and root morphology. The F8 and F4 formulas as compound fertilizers showed the potential of a high growth rate and high quality. The seedlings on which they were all applied had an excellent photosynthetic capacity and a well-developed root system. A correlation analysis showed that root traits were significantly correlated with some aboveground indices of seedlings (growth, biomass and nutrients, etc.), among which the root K concentration was very significantly correlated with photosynthetic capacity, and the root P was very significantly correlated with seedling biomass. Dipping roots mainly promoted the uptake of P and K nutrients by roots, which had a positive effect on seedling photosynthesis and the root system, and thus improved the growth increment and growth quality of seedlings. A principal component analysis showed that dipping roots significantly promoted the growth traits of seedlings, and the best-performing formula for dipping roots was F8 at one month of growth. F4 was the best choice for growth at two months. F4 showed excellent performance in all trait indices and was the only treatment where an increase in the rhizome-to-stem ratio occurred, indicating that the nutrient distribution of F4 seedlings was uniform and efficient, which compensated for the deficiency of the follow-up fertility of the quick-acting complex fertilizer. The scientific formula of soaking root fertilizer can be economically applied by dipping roots to synchronously promote early growth and quality of seedlings, which can provide a theoretical basis for the early large-scale cultivation of E. urograndis and other plants. [ABSTRACT FROM AUTHOR]