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The tetrazolium (TZ) test is a reliable but destructive method for identifying viable seeds. In this study, a non-destructive seed viability analysis method for Allium ulleungense was developed using multispectral imaging and stacking ensemble learning. Using the Videometerlab 4, multispectral imaging data were collected from 390 A. ulleungense seeds subjected to NaCl-accelerated aging treatments with three repetitions per treatment. Spectral values were obtained at 19 wavelengths (365–970 nm), and seed viability was determined using the TZ test. Next, 80% of spectral values were used to train Decision Tree, Random Forest, LightGBM, and XGBoost machine learning models, and 20% were used for testing. The models classified viable and non-viable seeds with an accuracy of 95–91% on the K-Fold value (n = 5) and 85–81% on the test data. A stacking ensemble model was developed using a Decision Tree as the meta-model, achieving an AUC of 0.93 and a test accuracy of 90%. Feature importance and SHAP value assessments identified 570, 645, and 940 nm wavelengths as critical for seed viability classification. These results demonstrate that machine learning-based spectral data analysis can be effectively used for seed viability assessment, potentially replacing the TZ test with a non-destructive method. [ABSTRACT FROM AUTHOR]

In the field of triplet–triplet annihilation upconversion (TTA-UC), the design of an optimized UC system with a high quantum yield at a low excitation power density is a challenging issue. To achieve this goal, it is essential to improve the triplet quantum yields (ΦT) and the UC quantum yields (ΦUC) of the triplet photosensitizers. In this study, we synthesized a novel series of donor–acceptor–heavy-atom (D–A–H) molecules where we have focused on pyrene, BODIPY, and halogen atoms (Cl, Br, and I) as D, A, and H moieties, respectively. The TTA-UC properties of the D–A–H molecules were examined, and their electrochemical properties and excited-state dynamics were investigated. The highest singlet oxygen and UC quantum yields were estimated for PY-BDP-2I (PY = pyrene and BDP = BODIPY) with the values of 0.93 and 4.84%, respectively. In addition, the threshold intensities (Ith) of PY-BDP-2Cl, PY-BDP-2Br, and PY-BDP-2I (112, 27, and 42 mW cm−2, respectively) were lower than that of PY-BDP (406 mW cm−2). In UC quantum yields, the iodine-containing samples (PY-BDP-2I and BEN-BDP-2I) show higher quantum yields than other compounds, which demonstrates that the introduction of iodine into the D–A–H photosensitizer system is an effective strategy for improving the TTA-UC performance. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) is known for its photochromic properties, making it useful for smart windows, displays, and sensors. However, its small bandgap leads to rapid recombination of electron–hole pairs, resulting in poor photochromic performance. This study aims to enhance the photochromic properties of WO3 by synthesizing hexagonal tungsten oxide via hydrothermal synthesis, which increases surface area and internal hydrates. Titanium oxide (TiO2) was adsorbed onto the tungsten oxide to inject additional charges and reduce electron–hole recombination. Additionally, polyvinylpyrrolidone (PVP) was used to improve dispersion in organic solvents, allowing for the fabrication of high-quality films using the doctor blade method. Characterization confirmed the enhanced surface area, crystal structure, and dispersion stability. Reflectance and transmittance measurements demonstrated significant improvements in photochromic properties due to the composite structure. These findings suggest that the introduction of TiO2 and PVP to tungsten oxide effectively enhances its photochromic performance, broadening its applicability in various advanced photochromic applications. [ABSTRACT FROM AUTHOR]

Submerged entry nozzle (SEN) clogging is investigated with an emphasis on the interfacial reaction between the nozzle refractory and the liquid steel. Within the context of carbothermically produced CO(g) being the main cause of the early stage SEN clogging, various SEN refractory materials are assessed in view of their impact on the initial clog deposit formation. A series of high‐temperature experiments are carried out to observe the interfacial reaction between the SEN refractory materials and the liquid steel: three oxide‐based and one oxide‐less refractory materials are employed. Ti‐free and Ti‐added ultra‐low C steel are reacted with these refractory materials. The reactivity of the refractories is assessed by 1) the morphology, composition, and thickness of the initial clog deposit and 2) the evolution of steel compositions. Decreasing SiO2 content in "oxide‐based" refractory is recommended. The "oxide‐less" refractory composed of AlON–BN–AlN is shown to be promising to suppress the early stage of SEN clogging. The present results would provide directions for designing the SEN refractory constitution to suppress the SEN clogging. [ABSTRACT FROM AUTHOR]

Developing high-energy-density electrodes for lithium ion batteries (LIBs) is of primary importance to meet the challenges in electronics and automobile industries in the near future. Conversion reaction-based transition metal oxides are attractive candidates for LIB anodes because of their high theoretical capacities. This review summarizes recent advances on the development of nanostructured transition metal oxides for use in lithium ion battery anodes based on conversion reactions. The oxide materials covered in this review include oxides of iron, manganese, cobalt, copper, nickel, molybdenum, zinc, ruthenium, chromium, and tungsten, and mixed metal oxides. Various kinds of nanostructured materials including nanowires, nanosheets, hollow structures, porous structures, and oxide/carbon nanocomposites are discussed in terms of their LIB anode applications.