A novel fluorescence sensor of NR-β-CD@AuNPs was prepared for the trace detection of nitrite in quantities as low as 4.25 × 10⁻³ μg∙mL⁻¹ in an aqueous medium. The fluorescence was due to the host-guest inclusion complexes between neutral red (NR) molecules and gold nanoparticles (AuNPs), which were modified by per-6-mercapto-beta-cyclodextrins (SH-β-CDs) as both a reducing agent and a stabilizer under microwave radiation. The color of the NR-β-CD@AuNPs changed in the presence of nitrite ions. A sensor was applied to the determination of trace nitrites in environmental water samples with satisfactory results.

Synergistic control of the emissions of air pollutants and CO₂ is critical to the dual challenges of air quality improvement and climate change in China. Based on the emission inventories of thermal power units in Beijing, Tianjin, and Hebei, this study analyzes the CO₂ and NO_X emission characteristics of these units, and identifies and quantifies the synergistic drivers affecting these emission trends. The inventory data show that, between 2010 and 2020, NO_X emissions were reduced by 86.1%, while CO₂ emissions were reduced by only 29.8%. Although significant progress has been made in reducing NO_X emissions through measures such as end-of-pipe treatment, controlling CO₂ emissions remains a difficult task. The index decomposition analysis reveals that economic growth is the main driver of CO₂ and NO_X emission growth, energy intensity reduction is the main driver of CO₂ emission reduction, and end-of-pipe treatment is the main driver of NO_X emission reduction. Currently, coal occupies about 87% of the energy consumption of thermal power units in the Beijing–Tianjin–Hebei region, and remains the main type of energy for synergistic emissions, and the potential for emission reduction in the energy structure remains huge. For NO_X emissions, it is expected that 90% of the reduction potential can be achieved through energy restructuring and end-of-pipe treatment. In conclusion, this high-precision unit-by-unit emission study confirms the effectiveness of the control policy for thermal power units in the region and provides some scientific reference for future policy formulation.

Synergistic control of emissions of air pollutants and CO2 is critical to the dual challenges of air quality improvement and climate change in China. Based on the emission inventories of thermal power units in Beijing, Tianjin, and Hebei, this study analyzes the CO2 and NOX emission characteristics of these units, identifies and quantifies the synergistic drivers affecting these emission trends. Inventory data show that between 2010 and 2020, NOX emissions were reduced by 86.1%, while CO2 emissions were reduced by only 29.8%. Although significant progress has been made in reducing NOX emissions through measures such as end-of-pipe treatment, controlling CO2 emissions remains a difficult task. The index decomposition analysis reveals that economic growth is the main driver of CO2 and NOx emission growth, energy intensity reduction is the main driver of CO2 emission reduction, and end-of-pipe treatment is the main driver of NOX emission reduction. Currently, coal occupies about 87% of the energy consumption of thermal power units in the Beijing-Tianjin-Hebei, and remains the main type of energy for synergistic emissions, and the potential for emission reduction in the energy structure remains huge. For NOX emissions, it is expected that 90% of the reduction potential can be achieved through energy restructuring and end-of-pipe treatment. In conclusion, the high-precision unit-by-unit emission study confirms the effectiveness of the control policy for thermal power units in the region and provides some scientific reference for future policy formulation.

The total control of major water pollutants (TCMWP) is a critical strategy for improving water quality in China, with the added benefit of yielding climate-related advantages. This study uses the emission factor method to quantify the reductions in pollutants and carbon emissions resulting from China’s implementation of TCMWP. A synergy scale for pollution and carbon reduction was constructed to assess the co-benefits of reducing the Chemical Oxygen Demand (COD) and ammonium nitrogen (NH₄⁺-N) and carbon dioxide (CO₂) emissions. Furthermore, to account for regional variations in energy structure regulation strategies, whether aggressive or unified, we developed Pollutant Synergistic Carbon Reduction Pathways at the Regional (R.PSCRP) model framework level to evaluate the carbon emission reduction potential of TCMWP during the “14th Five-Year Plan” period. The study revealed that China’s unified TCMWP employs different but highly effective combinations of emission reduction paths across different regions. Notably, new renovations and expansions of wastewater treatment facilities (NRE-WWTFS) and pipeline network construction and renovation (CR-PNK) together accounted for 89.3% of the total emission reduction. The construction of key water pollutant reduction projects plays a significant role in reducing carbon emissions at the district level compared to direct discharge practices. Additionally, indirect emissions resulting from TCMWP implementation account for approximately 50% of the total carbon reduction achieved. By aligning either harmonized or independent energy adjustment targets, regions were able to achieve substantial pollution and carbon reduction benefits, ranging from 7.5 to 8 million tons of CO₂-equivalent.