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Simple Summary: The Amur tiger is an endangered species in the world, and effective statistics on its individuals and population through re-identification will contribute to ecological diversity investigation and assessment. Due to the fact that the fur texture features of the Amur tiger contain genetic information, the main method of identifying Amur tigers is to distinguish their fur and facial features. In summary, this paper proposes a serial multi-scale feature fusion and enhancement network for Amur tiger re-identification, and designs a global inverted pyramid multi-scale feature fusion module and a local dual-domain attention feature enhancement module. We aim to enhance the learning of fine-grained features and differences in fur texture by better fusing and enhancing global and local features. Our proposed network and module have achieved excellent results on the public dataset of the ATRW. The Amur tiger is an important endangered species in the world, and its re-identification (re-ID) plays an important role in regional biodiversity assessment and wildlife resource statistics. This paper focuses on the task of Amur tiger re-ID based on visible light images from screenshots of surveillance videos or camera traps, aiming to solve the problem of low accuracy caused by camera perspective, noisy background noise, changes in motion posture, and deformation of Amur tiger body patterns during the re-ID process. To overcome this challenge, we propose a serial multi-scale feature fusion and enhancement re-ID network of Amur tiger for this task, in which global and local branches are constructed. Specifically, we design a global inverted pyramid multi-scale feature fusion method in the global branch to effectively fuse multi-scale global features and achieve high-level, fine-grained, and deep semantic feature preservation. We also design a local dual-domain attention feature enhancement method in the local branch, further enhancing local feature extraction and fusion by dividing local feature blocks. Based on the above model structure, we evaluated the effectiveness and feasibility of the model on the public dataset of the Amur Tiger Re-identification in the Wild (ATRW), and achieved good results on mAP, Rank-1, and Rank-5, demonstrating a certain competitiveness. In addition, since our proposed model does not require the introduction of additional expensive annotation information and does not incorporate other pre-training modules, it has important advantages such as strong transferability and simple training. [ABSTRACT FROM AUTHOR]

[Objective] Sludge production is abundant; however, its utilization rate remains low; co-gasification of sludge with coal is an important way to realize its resourcefulness and harmlessness. In industrial operations, gasification agents such as air and carbon dioxide primarily influence gasification, and the ash characteristics of the feedstock are crucial to ensure the long-term stable operation of the gasifier. The slagging characteristics of raw materials are closely related to their ash-melt properties, and the transformation of minerals is the essence of the change in the ash-melt properties. Currently, owing to the difference in the composition of raw materials, the evolutionary mechanism of the mineral transformation of the coal and sludge co-gasification process through the change in the sludge mixing ratio and the atmosphere on the mixing of the two remains unclear and lacks guidance for the change in the composition, which warrants further analysis. [Methods]In this paper, an experiment was designed for the mineral conversion and slagging characteristics analysis in the co-gasification process of coal and domestic sludge. The experiment involved the slagging characteristics of coal-sludge mixed samples, ash melting characteristics, and mineral conversion during co-gasification. Using anthracite and domestic sludge as raw materials, the two were mixed in different mass ratios. The characteristic temperature of ash melting was determined using an ash melting point tester. The basic-acid ratio, silica-aluminum ratio, and other evaluation criteria were used to evaluate the slagging characteristics. An oxidizing atmosphere and a weakly reducing atmosphere were employed as the environments for the co-gasification of coal and sludge, respectively. The high-temperature ash samples obtained from the co-gasification were characterized using X-ray diffractometry and Fourier transform infrared spectroscopy to analyze the changes in minerals. [Results] The experimental results revealed the following: 1) The characteristic temperature of coal ash melting remained higher. The characteristic temperature of ash melting decreased with increasing sludge mixing ratio. Among them, the melting characteristic temperature decreased most significantly when mixed with 20% sludge; 2) According to the discriminant indices such as alkaline-acid ratio, silica ratio, silica-aluminum ratio, and composite index, coal ash was associated with mild slagging, and domestic sludge ash belonged to severe slagging. After sludge mixing of over 50%, the mixed sample ash was associated with serious slagging; 3) The high content of mullite (Al6Si2O13) in coal ash was the primary reason for its high ash melting point. The blending of sludge increased the alkaline oxides such as CaO and MgO in the mixed samples, and the mullite content decreased rapidly, transforming into eutectics with lower melting points such as anorthite (CaAl2Si2O8). This was the main reason for the decrease in the melting temperature of the mixed ash sample; 4) Compared with the oxidizing atmosphere, the weak reducing atmosphere was more conducive to the formation of anorthite, and the coal could produce more anorthite by mixing a lower proportion of sludge. [Conclusions]Through this experiment, students can master the design method of mineral transformation and slagging characteristic experiment in the co-gasification process of coal and sludge mixed samples, which will help students to analyze and master the microscopic characterization methods and cultivate their innovative ability for the effective utilization of carbon-containing solid waste resources. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) hybrid perovskites have been garnering increasing attention across various fields due to their rich optical, electrical, optoelectronic, and magnetic properties. Current growth techniques only offer millimeter-scale or polycrystalline perovskites, which present a major barrier to the practical large-scale applications of these materials. In this study, we successfully prepared a series of BA2CuCl4–xBrx perovskite single-crystalline nanosheets with centimeter size using a controlled cooling growth method. Characterization results suggest that the obtained single-crystalline nanosheets are of high quality and that Br is uniformly doped. Moreover, these single-crystalline nanosheets exhibit ferromagnetic ordering at low temperatures, with the Curie–Weiss temperature increasing from 14.2 to 16.5 K as Br-doping concentration increases. Our approach provides a potential solution for the scalable synthesis and application of hybrid perovskites. At the same time, this family of 2D magnetic perovskites with tunable optical properties holds great potential for future spintronics applications. [ABSTRACT FROM AUTHOR]

Magnesium slag-based porous materials (MSBPM) were successfully synthesized using alkali activation and foaming methods as an effective adsorbent for Pb2+ in solution. The effects of foaming agent type, foaming agent dosage, alkali dosage, and water glass modulus on the properties of the MSBPM were studied, and the micromorphology and porosity of the MSBPM were observed using microscopy. The influence of pH value, initial concentration, and adsorbent dosage on the Pb2+ adsorption was investigated. The results showed that a porous material (MSBPM-H2O2) with high compressive strength (8.46 MPa) and excellent Pb2+ adsorption capacity (396.11 mg·g−1) was obtained under the optimal conditions: a H2O2 dosage of 3%, an alkali dosage of 9%, a water glass modulus of 1.3, and a liquid–solid ratio of 0.5. Another porous material (MSBPM-Al) with a compressive strength of 5.27 MPa and the Pb2+ adsorption capacity of 424.89 mg·g−1 was obtained under the optimal conditions: an aluminum powder dosage of 1.5‰, an alkali dosage of 8%, a water glass modulus of 1.0, and a liquid–solid ratio of 0.5. When the pH of the aqueous solution is 6 and the initial Pb2+ concentrations are 200~500 mg·L−1, the MSBPM-H2O2 and MSBPM-Al can remove more than 99% of Pb2+ in the solution. The adsorption process of both materials followed the Langmuir isotherm model and pseudo-second-order kinetic model, indicating that the adsorption process was a single-molecule layer chemical adsorption. [ABSTRACT FROM AUTHOR]