Human settlements lay the basis for urban sustainable development and embody comprehensive urban competitiveness. Based on data from the period 2010–2019, the entropy value method, global spatial correlation, and local spatial correlation are adopted to systematically analyze the overall level and spatial–temporal pattern of human settlement quality in Beijing. In particular, this study sought to uncover the factors that influence human settlement quality in Beijing by using the panel data model. The results show that the quality of human settlements in Beijing has generally followed an upward trend, with slow growth and a slight decline since 2017. Despite significant spatial positive correlations and stable local spatial self-correlation, the spatial difference is still evident, and regional correlation needs further improvement. Medical resources, economic development, public services, governance investment, and infrastructure are significantly and positively correlated with human settlement quality, while population growth is significantly and negatively correlated with it. Based on this study, specific recommendations are proposed which can be used as a reference for Beijing and other cities’ human settlement construction and its improvement.

By employing phase change slurry (PCS) as working fluid for the heat pipe solar PV/T system, the study is designed to investigate the electrical and thermal energy performance of the system. Meanwhile, through examining the performance difference between water-based and PCS-based heat pipe solar PV/T systems, 30% alkyl hydrocarbon PCS is proved to be a suitable working fluid for optimized energy performance based on the combined consideration of the thermophysical and rheological properties. Both static and dynamic stability tests show that 30% alkyl hydrocarbon PCS has a good stability for low-temperature thermal energy storage. A testing rig is constructed consisting of two identical heat pipe solar PV/T cogeneration systems A and B, in which water and 30% alkyl hydrocarbon PCS are, respectively, employed as working fluids; the energy performance of those two PV/T systems are investigated and compared with each other under the same testing condition. The results indicate that the application of PCS to the heat pipe PV/T system leads to a significant improvement in thermal performance and a modest growth in electrical performance. The daily heat gains and overall average efficiency of system B are 4.2 MJ/m² (per unit area of PV/T panel) and 59.3%, respectively, 27.3% and 9.3% higher than those of system A. Per unit area of the heat pipe PV/T panel could produce 55.2 L domestic hot water of about 45°C on a sunny day.

The ecological behavior of property management enterprises is crucial to the performance of green buildings. The understanding of property management enterprises’ ecological behavior, however, is rather limited. The purpose of this paper is to analyze the mechanism of the affecting factors upon the ecological behavior of property management enterprises. The qualitative analysis method was used to collect and identify the influencing factors, which were further classified as those of stimulus, status, scenario, and result. A theoretical model of the action mechanism of influencing factors and related hypotheses has been constructed based on the planned behavior theory. The proposed hypotheses have been empirically analyzed by the quantitative analysis of a questionnaire survey. The results indicate that there are significant differences in ecological behavior implementation under different status factors, while the impact of enterprise nature on property management ecological behavior is not significant. Regarding the stimulus factors, market pressure and government regulation are the main external incentive factors. The scenario factors could be resistant forces and moderate the implementation of ecological behavior. For the result factors, property management enterprises pay attention to whether the implementation of ecological behavior can produce direct benefits. The research findings constitute valuable references for further development of the property management industry.

Population ageing is intensifying pressure on elderly-care provision in megacity suburbs, but spatially explicit evidence on who benefits and where gaps persist remains limited. Using Daxing District, Beijing, as a case study, under the 15-min community living circle framework, we integrate cleaned elderly-care facility POIs from the municipal government portal (209 points), census-calibrated age-stratified WorldPop 100 m grids, and an OpenStreetMap road network to evaluate walking-based supply–demand matching. Kernel density estimation (KDE) characterizes facility agglomeration; the Gaussian Two-Step Floating Catchment Area (Ga2SFCA) method (1 km threshold) measures accessibility for two cohorts (60–80 and 80+); and global Moran’s I with bivariate LISA identifies spatial coupling between accessibility and elderly population density. The results indicate the following: (1) pronounced spatial imbalance—facilities are concentrated in the northwest and east but remain sparse in central and southern areas, while elderly population density follows a center–periphery gradient, peaking at 12,000 persons/km² in core areas (e.g., Jiugong and Huangcun); (2) clear accessibility stratification—overall accessibility is low and spatially clustered, yet the 80+ cohort (13.6% of the elderly population) exhibits markedly higher accessibility than the 60–80 cohort; and (3) differentiated coupling types—global bivariate Moran’s I = 0.773143 (p < 0.01), with LISA dominated by low-demand–low-accessibility (LL) areas and additional high-demand–low-accessibility (HL) shortage zones and low-demand–high-accessibility (LH) potential redundancy zones, while HH areas are scarce. These diagnostics support zone-specific gap filling to mitigate spatial inequities and age–structural mismatches.