This study (June 2022-July 2023) investigates the atmospheric concentrations of carbonaceous species, including organic carbon (OC) and elemental carbon (EC), in PM in two major cities in Kazakhstan. Samples were collected from two sites in Almaty (Seifullin and KazNU) and one in Astana. The results showed that Almaty had significantly higher annual average concentrations of OC (10.8 and 10.5 μg/m) and EC (1.68 and 1.87 μg/m) compared to Astana (OC: 7.1 μg/m, EC: 0.61 μg/m). Both cities exhibited pronounced seasonal variations, with significantly elevated concentrations (1.5-3.4 times for OC, 2.1-4.8 times for EC) during the heating season compared to the non-heating season. This indicates a significant influence of coal and biomass combustion for heating on carbonaceous aerosol concentrations. Both cities' OC/EC ratios varied widely (2.6-39.4), showing strong positive correlations (0.61-0.94) across all seasons except summer, suggesting a common primary emission source. Primary organic carbon dominated OC levels in winter (71-74%), whereas secondary organic carbon contributed significantly to OC concentrations in summer (43-50%). Higher OC-EC concentrations correlated with lower atmospheric visibility values. The OC-EC contributions to the total light extinction coefficient were estimated to be 15.3-15.9% for Almaty and 12.0% for Astana stations.
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http://dx.doi.org/10.1016/j.chemosphere.2024.143968 | DOI Listing |
Environ Sci Pollut Res Int
January 2025
Department of Environmental Biotechnology, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Akademicka Str. 2, 44-100, Gliwice, Poland.
Various novel technologies are currently under development aimed at improving bio-methane output to tackle challenges related to process stability, biogas production, and methane quality in the anaerobic digestion (AD) process. The management of substrate type, temperature, pH, hydraulic retention time (HRT), organic loading rate (OLR), and inoculum origin is essential for ensuring process effectiveness, minimizing inhibition, and maximizing production of biogas and methane yield. The review emphasizes sustainability, focusing on the environmental and economic benefits of anaerobic digestion, including the reduction of greenhouse gas (GHG) emissions, the minimization of landfill waste, and the provision of renewable energy sources.
View Article and Find Full Text PDFACS Nano
January 2025
Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology, College of Materials Science and Engineering, Hunan University, Changsha 410082, China.
SiO-based anodes, considered the most promising candidate for high-energy density batteries, have long been bothered by mechanical integrity issues. Research efforts focus on particle modifications, often overlooking the enhancement of interparticle connections, which can reduce the active material content within the electrode. Herein, an integrated electrode with strong covalent bonding at the electrode scale is designed, achieving excellent mechanical stability with ∼95 wt.
View Article and Find Full Text PDFAppl Environ Microbiol
December 2024
Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany.
Unlabelled: The rising atmospheric concentration of CO is a major concern to society due to its global warming potential. In soils, CO-fixing microorganisms are preventing some of the CO from entering the atmosphere. Yet, the controls of dark CO fixation are rarely studied .
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
State Key Laboratory Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhu Road South, Nanjing 211816, China.
The cycloaddition of CO to epoxide (CCE) reactions produce valuable cyclic carbonates useful in the electrolytes of lithium-ion batteries, as organic solvents, and in polymeric materials. However, halide-containing catalysts are predominantly used in these reactions, despite halides being notoriously corrosive to steel processing equipment and residual halides also having harmful effects. To eliminate the reliance on halides as cocatalyst in most CCE reactions, halide-free catalysts are highly desirable.
View Article and Find Full Text PDFSoft Matter
January 2025
Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), School of Materials Science & Engineering, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.
Flexible two-dimensional nickel-cobalt metal-organic frameworks/graphene oxide/carbon nanotubes (2D NiCo-MOF/GO/CNTs) hybrid films have been designed and prepared as high-performance supercapacitor electrode materials vacuum filtration. The 2D NiCo-MOF nanosheets serve as the main source of capacitance for the hybrid films, while CNTs function as both the conductive network, enhancing the electrical conductivity of the MOFs, and the binder, linking the 2D NiCo-MOF nanosheets and GO. When the mass ratio of 2D NiCo-MOF, GO, and CNTs is 2 : 1 : 0.
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