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Due to the inherent metals (Cu, As and Cr) in preserved wood waste (CCA-treated wood waste) that pose a risk to both the environment and human health, it is crucial to dispose of CCA-treated wood properly. Carbon materials have received widespread attention for their high porosity, renewability and simplicity of fabrication. This work presents a simple and effective process for producing carbon materials from leftover CCA-treated wood (chromated copper arsenate). Utilizing CCA-treated wood derived carbon (CCA-BC) and activating it with KOH (CCA-AC), electrode materials for supercapacitor applications were created and its electrochemical characteristics were investigated. The resulting material combines the conductivity of the metal in preserved wood with the good porosity provided by carbon materials. Compared with common wood biomass, carbon (W-BC) and common wood activated carbon (W-AC), CCA-BC and CCA-AC have better electrochemical properties. After being pyrolyzed at 600 °C for two hours, CCA-AC performed optimally electrochemically in 1 M Na2SO4 electrolyte, demonstrating a 72% capacity retention rate after 2000 charge and discharge cycles and a specific capacity of 76.7 F/g. This study provides a novel approach for the manufacture of supercapacitor electrodes, which also allows preserved wood waste an environmentally nondestructive form of elimination. [ABSTRACT FROM AUTHOR]

Rapid urbanization threatens the ecological environment and quality of life by significantly altering land use and land cover (LULC) and heat distribution. One of the most significant environmental consequences of urbanization is the urban heat island effect (UHI). This study investigated the spatiotemporal characteristics of the SUHI and its relationship with land use types from 2000 to 2020 in Urumqi City, located in an arid and semi-arid region of northwestern China. Additionally, the ordinary least squares (OLS) and geographically weighted regression (GWR) models were used to quantify the relationship between the land surface temperature (LST) and influencing factors. The results showed that the area of the lower surface temperature classes has decreased significantly. In comparison, the area of the higher surface temperature classes has experienced a steady rise over the last two decades. From 2000 to 2020, the share of the area occupied by the temperature range <30 °C decreased by 67.09%. In addition, the LST varied significantly from one category of land use to another. The average LST of built-up land and unused land was higher than the average LST of other land use types in all years, while the average LST of grassland, forest land, and water bodies was significantly lower. Finally, the results of the GWR model showed that R2 and adjusted R2 of the GWR were 0.75 and 0.73, obviously larger than the 0.58 of the OLS models. The GWR model's higher R2 and adjusted R2 compared to the OLS model indicates that the relationship between LST and the influencing factors underlying the model may exhibit spatial non-stationarity, and the GWR model performs better than the OLS model. The results of both OLS and GWR models show that the normalized difference vegetation index (NDVI) and slope were negatively correlated with LST, while the urban index (UI) and normalized difference built-up index (NDBI) were positively correlated with LST. The findings of the study indicate that increasing green spaces and limiting the unplanned expansion of urban areas are effective measures to mitigate the UHIs in the study area. The results of the study may provide valuable insights into the spatiotemporal characteristics of the UHI and its drivers. Understanding the spatiotemporal characteristics of the UHI can help urban planners, policymakers, and scientists develop more effective urban cooling strategies and improve the urban thermal environment. [ABSTRACT FROM AUTHOR]

Recently, two Middle East respiratory syndrome coronavirus (MERS-CoV) closely related to bat merbecoviruses, NeoCoV and PDF-2180, were discovered to use angiotensin-converting enzyme 2 (ACE2) for entry. The two viruses cannot use human ACE2 efficiently, and their host range and cross-species transmissibility across a wide range of mammalian species remain unclear. Herein, we characterized the species-specific receptor preference of these viruses by testing ACE2 orthologues from 49 bats and 53 non-bat mammals through receptor-binding domain (RBD)-binding and pseudovirus entry assays. Results based on bat ACE2 orthologues revealed that the two viruses were unable to use most, but not all, ACE2 from Yinpterochiropteran bats (Yin-bats), which is distinct from NL63 and SARS-CoV-2. Besides, both viruses exhibited broad receptor recognition spectra across non-bat mammals. Genetic and structural analyses of bat ACE2 orthologues highlighted four crucial host range determinants, all confirmed by subsequent functional assays in human and bat cells. Notably, residue 305, participating in a critical viral receptor interaction, plays a crucial role in host tropism determination, particularly in non-bat mammals. Furthermore, NeoCoV and PDF-2180 mutants with enhanced human ACE2 recognition expanded the potential host range, especially by enhancing their interaction with an evolutionarily conserved hydrophobic pocket. Our results elucidate the molecular basis for the species-specific ACE2 usage of MERS-related viruses and shed light on their zoonotic risks. [ABSTRACT FROM AUTHOR]

Let n and k be positive integers with $n\ge k+1$ and let $\{a_i\}_{i=1}^n$ be a strictly increasing sequence of positive integers. Let $S_{n, k}:=\sum _{i=1}^{n-k} {1}/{\mathrm {lcm}(a_{i},a_{i+k})}$. In 1978, Borwein ['A sum of reciprocals of least common multiples', Canad. Math. Bull. 20 (1978), 117–118] confirmed a conjecture of Erdős by showing that $S_{n,1}\le 1-{1}/{2^{n-1}}$. Hong ['A sharp upper bound for the sum of reciprocals of least common multiples', Acta Math. Hungar. 160 (2020), 360–375] improved Borwein's upper bound to $S_{n,1}\le {a_{1}}^{-1}(1-{1}/{2^{n-1}})$ and derived optimal upper bounds for $S_{n,2}$ and $S_{n,3}$. In this paper, we present a sharp upper bound for $S_{n,4}$ and characterise the sequences $\{a_i\}_{i=1}^n$ for which the upper bound is attained. [ABSTRACT FROM AUTHOR]

Homogeneous Catalysis. In their Research Article (e202412193) Ming‐Hua Xu et al. report the rational design of a novel cationic rhodium(I)/chiral diene catalyst to achieve the challenging enantioselective B‐H and O‐H bond insertion of diarylcarbenes...By Weici Xu; Takeshi Yamakawa; Meiling Huang; Peilin Tian; Zhigen Jiang and Ming‐Hua XuReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

Defect engineering is considered an effective strategy to improve the electrochemical performance of batteries because of its ability to promote ion diffusion and increase reactive sites in electrode materials. Twin boundaries as interfacial defects offer new opportunities for ion transport in nanomaterials. In this work, CdxZn1−xS with twin boundaries (CdxZn1−xS-B) was designed and fabricated based on the theories of crystal structure analysis and density functional theory (DFT) calculations. We demonstrate that the introduction of Zn into CdS to form CdxZn1−xS-B enables fast lithium-ion diffusion and enhances structural stability. Its reversible specific capacity is approximately four times that of its corresponding single metal sulfide electrode and the cycle stability is significantly better than that of CdxZn1−xS without twin boundaries. Notably, Cd0.7Zn0.3S-B delivers a high specific capacity of 404.8 mA h g−1 at 2.0 A g−1 after 1900 cycles, and the Cd0.7Zn0.3S-B‖‖LiFePO4 full cell maintained a capacity retention of 84.3% after 150 cycles at 500 mA g−1. Cd0.7Zn0.3S-B also shows excellent sodium storage performance. This study demonstrates that designing electrode materials via introducing twin boundaries can promote the development of next generation rechargeable batteries. [ABSTRACT FROM AUTHOR]