In the past decade, the application of photocatalytic sterilization technology for indoor air disinfection has been extensively investigated. However, selecting suitable photocatalysts with high sterilization efficiency remains a challenge. By doping and incorporating metals, the bandgap can be narrowed, thereby avoiding the recombination of photogenerated charges. This study compares the photocatalytic sterilization performances of three commonly used photocatalysts (TiO ₂ –Ag, MnO ₂ –TiO ₂ , and MnO ₂ –CeO ₂ ) in a controlled laboratory setting. The results demonstrated that TiO ₂ –Ag exhibited the best sterilization performance. Within 20 min, the concentration of Serratia marcescens (the test bacterium) decreased logarithmically with respect to ln3.78 under a light intensity of 640 W/m ² . During the bacterial inactivation process, Serratia marcescens is inactivated by the destruction of its cell membrane, which decreases its enzyme activity and releases its cell contents. This can be attributed to the efficient generation of reactive oxygen species (O ₂ • ^– and •OH) and the thermal effect. Spectral regulation has the most significant impact on the sterilization efficiency of MnO ₂ –TiO ₂ , reducing the probability of photocatalytic materials being excited. A significance analysis indicated that light intensity, exposure duration, photocatalyst type, dilution of used photocatalysts, and spectral regulation substantially impact photocatalytic sterilization outcomes. Density functional theory (DFT) was used to elucidate the mechanism for the adsorption and catalysis of bacterial cell membranes at the atomic scale.

Buildings account for a significant proportion of total energy consumption. The integration of renewable energy sources is essential to reducing energy demand and achieve sustainable building design. The use of solar energy has great potential for promoting energy efficiency and reducing the environmental impact of energy consumption in buildings. This study examines the applications of photovoltaic and solar thermal technologies in the field of architecture, demonstrating the huge potential of solar energy in building applications. To ensure a fresh and thorough review, we examine literature that encompasses the advancements made in the utilization of solar energy in buildings over the past decade. The key factors to consider in this study are reliability, performance, cost and aesthetics in real applications of photovoltaic and solar thermal technologies in the field of architecture, which have a significant impact on people’s acceptance of solar energy technology. Recent developments in feasible and effective optimization solutions for solar energy technologies are summarized. Accurate and convenient simulation techniques are also summarized for reference. The results show that the rapid progress of BIPV systems is fueled by advancements in three crucial areas: enhancing solar cell and module efficiency, reducing manufacturing costs and achieving a competitive levelized cost of electricity. The results can provide researchers with a reference for understanding recent technological developments in the integration of solar energy into buildings.

The combustion of diesel fuel in internal combustion engines faces challenges associated with excessive emissions of pollutants. A direct solution to this issue is the incorporation of cleaner energy sources. In this study, a numerical model was constructed to investigate the characteristics of ammonia–diesel dual-fuel application in a medium-speed diesel engine. Effects of ammonia–diesel blending ratios on engine performance and emissions were investigated. The results indicate that for this engine model, the optimal diesel energy ratio is about 22%. When the diesel energy ratio is less than 22%, the engine’s output performance is significantly affected by the diesel energy ratio, while above 22%, the influence of the intake becomes more pronounced. When the diesel energy ratio is below 16%, the cylinder cannot reach combustion conditions. Diesel energy ratios below 22% can cause ammonia leakage. With increasing diesel energy ratio, the final emissions of carbon oxides increase. With a higher diesel energy ratio, NO emissions become lower. When the diesel fuel energy ratio exceeds 22%, the N₂O emissions can be almost neglected, while below 22%, with poor combustion conditions inside the cylinder, the N₂O emissions will increase.

In regions experiencing severe cold, inadequate ventilation during winter months often leads to increased concentrations of indoor pollutants. While there have been several studies on indoor particulate matter and inorganic pollutants in such regions, bioaerosol pollution has not been as extensively investigated. This study examines the indoor bioaerosol situation in a university located in one of the severe cold regions in China, focusing on bacteria as a representative pollutant. It investigated random samples of an office and a dormitory (including washrooms) and spanned heating and nonheating periods. The findings indicated that bacterial abundance in the dormitory and office was approximately equivalent. The predominant airborne bacterial communities identified were Proteobacteria, Bacteroidota, Actinobacteriota, Firmicutes, and Myxococcota. Opening windows effectively reduced bacterial concentrations during both heating and nonheating periods. When windows remained closed, bacterial concentrations exceeded the standard by 9.1% during the nonheating period and by 14.3% during the heating period. Furthermore, temperature and relative humidity influenced bacterial particle size, activity, and consequently, aerosol concentrations. In the office, the highest percentage of bioaerosols was observed in particle sizes <1.1 and 1.1–2.1 μm, with smaller percentages observed in other particle sizes. Conversely, the percentage of particle sizes 2.1–3.3 μm in the dormitory was higher. The highest bacterial aerosol concentrations were detected in the morning in both the dormitory and office, during heating and nonheating periods. Bacterial concentrations in the office were lower on weekends than on weekdays, whereas in the dormitory, concentrations were higher on weekends than on weekdays. The above results indicate that indoor bacterial aerosol pollution is serious in winter in severe cold regions, which needs more attention.