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This review analyzes the literature data and the results of studies of the Pt/CeO2‐based catalysts that are capable of providing the low‐temperature CO oxidation (LTO CO). The review summarizes the catalytic characteristics and the main properties of Pt/CeO2‐based catalysts necessary for the low‐temperature oxidation at T<50 °C. Analysis of the literature data on the use of physical methods of investigation and their correlation with the activity of Pt/CeO2 catalysts allowed us to conclude that the main active forms of platinum are small metallic clusters, single atoms Pt2+‐SA and oxide clusters PtOx interacting with ceria nanoparticles. It has been established that the most active forms are PtOx clusters, which provide a high reaction rate in the temperature range from −50 to +50 °C. Forms of ionic Pt2+ with different coordination with oxygen ensure the activity of catalysts starting at temperatures above 100 °C. Finally, small metallic clusters occupy an intermediate position, providing activity above 0 °C, but their instability and gradual transition to the oxidized state Pt2+/PtOx are noted. At the conclusion of the review, the results of mathematical modeling demonstrate the correct kinetics description of the low‐temperature CO oxidation based on the Mars‐van Krevelen and associative mechanisms. [ABSTRACT FROM AUTHOR]

Metallic clusters, ranging from 1 to 2 nm in size, have emerged as promising candidates for creating nanoelectronic devices at the single-cluster level. With the intermediate quantum properties between metals and semiconductors, these metallic clusters offer an alternative pathway to silicon-based electronics and organic molecules for miniaturized electronics with dimensions below 5 nm. Significant progress has been made in studies of single-cluster electronic devices. However, a clear guide for selecting, synthesizing, and fabricating functional single-cluster electronic devices is still required. This review article provides a comprehensive overview of single-cluster electronic devices, including the mechanisms of electron transport, the fabrication of devices, and the regulations of electron transport properties. Furthermore, we discuss the challenges and future directions for single-cluster electronic devices and their potential applications. [ABSTRACT FROM AUTHOR]

Hypothesis-driven experiments have been conducted to explore the spatial variability and potential ecological risk indices (RIs) of potentially toxic elements (PTEs) in untreated in situ effluent continuously discharged downstream by the Kumasi Abattoir Ghana (KAG). The study focused on seven PTEs  nickel (Ni), lead (Pb), cadmium (Cd), manganese (Mn), zinc (Zn), copper (Cu), and iron (Fe), based on these hypotheses: (i) Variations in PTE levels may be significant in the effluent; (ii) Comparative RI assessments based on the three background values  natural background values (NBVs) for freshwater, maximum admissible concentrations (MACs), and reference values (RVs) provide objective evaluations; and (iii) PTEs’ cluster distances are linked to RIs. Effluent samples were randomly collected in quintuplicates from the drainage receptacle and analyzed using standard methods. The spatial variability of PTEs was investigated using divisive hierarchical cluster analysis (DHCA). The RIs and their uncertainties were computed using Hakanson's equations and standard deviation (SD). PTE dispersion was analyzed using the coefficient of variation (CV). Analysis of variance (ANOVA) was employed to test for the significance of hypotheses 1 and 2, complemented by Scheffé's post-hoc test where significance was detected. Hypothesis 3 was investigated by analyzing PTE cluster distances and RIs based on Pearson's correlation metric. The DHCA produced two clusters Cd–Cu–Mn–Ni and Zn-(Fe)-Pb. The CVs (< 50 %) indicated medium variability, relatively uniform spatial distributions, and minimal fluctuations. High to very high RIs ± SDs obtained were 300 ± 57.5 (MACs), 2900 ± 500 (RVs), and 7666 ± 2980 (NBVs). The ANOVA yielded significant results for both hypotheses, while moderate to high correlations were obtained for the third hypothesis. While RIs provided compelling evidence of inimical effluent, the study highlights the influence of background values on RIs. It further suggests that the PTE cluster distances may be used as surrogates for the RIs.