Educational technology is the most closely related discipline with information technology, which has made great contributions to the development of our country’s education. In the context of the new ...liberal arts construction, educational technology majors in our country face an important era topic. The new liberal arts in the modern sense is under the background of the new scientific and technological revolution. It emphasizes the integration of disciplines and the innovation of knowledge theory in the discipline connotation, and emphasizes the cultivation of all mankind in the goal and task, so as to guide and serve the needs of society. In view of this, this paper analyzes the transmutation status of educational technology in colleges and universities in our country under the background of the new liberal arts construction, and analyzes the development path from three aspects: understanding the data change of educational technology, valuing the integration of humanistic spirit teaching and passing on the outstanding traditional culture, so as to provide certain guidance for the society to cultivate professionals in educational technology.
Urban heat island (UHI) often cause negative impact and has been linked to heart stroke rate, morality, human comfort, energy consumption and air pollution. Fortunately, urban green spaces have been ...considered as an effective element to mitigate UHI through their cooling effect. However, further empirical research is necessary in order to efficiently guide the design and planning of urban green space. We observed the impacts of urban park's tree, grass and waterbody on microclimate inside the Olympic park of Beijing during summer days. The results indicated that, on average, the park was 0.48–1.12 °C cooler during the day, as well as increased air humidity 2.39–3.74% and reduced human comfort index 1.02–2.43 to generate more comfortable thermal environment. Urban park's cluster trees with short ground vegetation generated higher cooling effect than single trees, grass and waterbodies; proper irrigation regime enhanced the cooling effect of grasses, even the irrigated grass have similar cooling effect with small waterbody on sunny, windless summer days. Therefore, we advise to increase undergrowth coverage and grass irrigation management in order to take advantage of cooling effect of urban parks.
•The green space area reduced by 199km2 and became fragmented from 2000 to 2010.•The annual runoff reduction volume ranged from 132millionm3 to 198millionm3.•The rainwater runoff reduction rate ...decreased by 6% with the land cover changes.•The green space with larger LPI and AI is suitable for flooding risk reduction.
The effects of urban green spaces on stormwater runoff have increasingly attracted attention because of climate change and rapid urbanization conditions. This study investigates the spatial–temporal changes of urban green spaces in Beijing and estimates their effects on rainwater runoff reduction based on an empirical model. Results indicate that green spaces in Beijing decreased by 199km2 from 2000 to 2010 and that landscape patches became increasingly isolated and fragmented. The volume of rainwater runoff controlled by urban green spaces first increased and then decreased with the increase in summer rainfall. The runoff reduction rate continuously decreased from 23% in 2000 to 17% in 2010, which is mainly attributed to the composition changes in urban green spaces. In addition, an immense regional difference that is closely related to the changes in the largest patch and aggregation indices of urban green spaces are observed in different regions. This study recommends an optimal landscape pattern of urban green spaces for the planning and management of green spaces in highly urbanized areas.
Urban green space has been considered as an ecological measure to mitigate urban heat islands (UHI). However, few studies investigate the cooling effect of the adjacent area of the urban park; as the ...transition region from a green space to a hardened surface where more complex heat exchange occurs, it deserves to be paid more attention. This paper examines the relationship between the urban greening patterns and the cooling effect in the surrounding areas of the Olympic Forest Park in Beijing. Results showed that the forestland and waterbodies could cool 6.51% and 12.82% of the impervious surface temperatures, respectively. For every 10% increase in the green space ratio, the land surface temperature drops by 0.4°C, and per kilometer increase in the distance from the forest park, the land surface temperature increases by 0.15 °C. The aggregation index (AI) and largest patch index (LPI) of the green space patterns presented a strong negative correlation with surface temperature. This study confirms the cooling effects in the adjacent area of the urban park and highlights their dependence on urban greening patterns. Therefore, we should not only develop more green spaces but also scientifically plan their spatial configuration in the limited urban land for the improvement of the cooling effect.
Urban green spaces have been proven to significantly decrease ambient air temperature and mitigate heat islands created by urbanization. However, the environmental benefits of cooling provided by ...urban green spaces have rarely been measured. In this paper, we estimated the energy-savings and emission-reduction contribution of urban green spaces in Beijing, applying a empirical model. Our calculations suggest urban green spaces play a major role in reducing energy demand and increasing CO2 sequestration. Urbanized Beijing has 16,577 ha of green space which could absorb 3.33 × 1012 kJ of heat via evapotranspiration during the entire summer. The cooling effect reduced the air conditioning demand by 3.09 × 108 kWh which amounts to a 60% reduction in net cooling energy usage in Beijing. The annual reduction in CO2 emissions from power plants associated with electricity saving would reach 243 thousand tons with an average of 61 kg/(ha day). Also, the cooling effect and the environmental benefits of urban green space in Beijing largely depend on the green space's structure and size. Urban managers and landscape planners should take advantage of this research to plan, design and manage green spaces in heat island areas.
•The cooling effect and environmental benefits of Beijing's green space were analyzed.•Green spaces can absorb 3.33 × 1012 kJ of heat via evapotranspiration during summer.•The cooling effect annually reduced demand for air conditioning by 3.09 × 108 kWh.•Annual reduction in CO2 emissions from power plants could exceed 243 thousand tons.•Cooling effect and its contribution via green space structure and size are discussed.
The cooling effect of green spaces as an ecological solution to mitigate urban climate change is well documented. However, the factors influencing the microclimate in the built environment around ...forest parks, diurnal variations of their impact and their degree of importance have not been explicitly addressed. We attempted to quantify how much various landscape parameters, including land cover and spatial location, impact the ambient air and surface temperature in the area around Beijing’s Olympic Forest Park. Data were taken along strategically located traverses inside and outside the park. We found: (1) The air temperature during the day was 1.0–3.5 °C lower in the park than in the surrounding area; the surface temperature was 1.7–4.8 °C lower; air humidity in the park increased by 8.7–15.1%; and the human comfort index reduced to 1.8–6.9, all generating a more comfortable thermal environment in the park than in the surrounding area. (2) The distance to the park and the green space ratio of the park’s surrounding area are significant factors for regulating its microclimate. A 1 km increase in distance to the park caused the temperature to increase by 0.83 °C; when the green space ratio increased by 10%, the temperature dropped by 0.16 °C on average. The impact of these two parameters was more obvious in the afternoon than in the middle of the day or in the morning. The green space ratio could be used for designing a more stable thermal environment. (3) Land cover affects surface temperature more than it does air temperature. Our data suggest that an urban plan with an even distribution of green space would provide the greatest thermal comfort.
Land use and related pressures have reduced local terrestrial biodiversity, but it is unclear how the magnitude of change relates to the recently proposed planetary boundary ("safe limit"). We ...estimate that land use and related pressures have already reduced local biodiversity intactness–the average proportion of natural biodiversity remaining in local ecosystems–beyond its recently proposed planetary boundary across 58.1% of the world's land surface, where 71.4% of the human population live. Biodiversity intactness within most biomes (especially grassland biomes), most biodiversity hotspots, and even some wilderness areas is inferred to be beyond the boundary. Such widespread transgression of safe limits suggests that biodiversity loss, if unchecked, will undermine efforts toward long-term sustainable development.
A liquid-phase chemical process for preferential growth of long ZnO nanowires has been developed. The process effectively suppresses homogeneous nucleation and prevents formation of ZnO particles in ...the bulk solution while allowing rapid growth of ZnO nanowires on seeded substrates. With this process, ZnO nanowires on seeded substrates can grow at an initial rate over 10 times faster than that in the previous process with bulk ZnO precipitation and nanowires of more than 30 μm can be readily obtained within 10 h. The ultralong ZnO nanowires enable fabrication of dye-sensitized solar cells (DSCs) with up to 33 μm thick sensitizing films (the thickest in the literatures) while maintaining high electron collection efficiency, which results in greatly improved performance compared to previously reported ZnO nanowire-based DSCs.
Lead halide perovskite materials are thriving in optoelectronic applications due to their excellent properties, while their instability due to the fact that they are easily hydrolyzed is still a ...bottleneck for their potential application. In this work, water-resistant, monodispersed and stably luminescent cesium lead bromine perovskite nanocrystals coated with CsPb2Br5 were obtained using a modified non-stoichiometric solution-phase method. CsPb2Br5 2D layers were coated on the surface of CsPbBr3 nanocrystals and formed a core-shell-like structure in the synthetic processes. The stability of the luminescence of the CsPbBr3 nanocrystals in water and ethanol atmosphere was greatly enhanced by the photoluminescence-inactive CsPb2Br5 coating with a wide bandgap. The water-stable enhanced nanocrystals are suitable for long-term stable optoelectronic applications in the atmosphere.
The insufficient information on water conservation dynamics and potential in ecological engineering areas often restrict the selection and implementation of ecological restoration measures in arid ...and semiarid climates. Based on the regional water balance equation and GIS spatial analysis tools, this article assessed the spatial-temporal changes in water conservation in Xilin Gol League, a representative region of the Beijing–Tianjin Sandstorm Source Control Project Area. The results indicated that the yearly amount of water conservation in Xilin Gol League reached 1.27 billion cubic meters, and annual precipitation of approximately 6.36 mm was retained per hectare. The water conservation capacity in Xilin Gol League showed a notably increasing tendency during the period of 2000–2015 and increased from west to east. The northeast of East Ujimqin Banner had the highest capacity, contributing 16.19% of the total water conservation amount. Compared to 2000, approximately 65.86% of Xilin Gol League presented water conservation capacity increases in 2015, 15.25% of which were significant. The water conservation in Xilin Gol League correlated with the changes in precipitation, temperature, and vegetation coverage, and unfavorable changes in these factors led to a significant decline in regional water conservation capacity. Therefore, multiple ecological restoration strategies are proposed for the improvement of water conservation capacity in the low-efficiency areas.
•Dynamic changes in water conservation in ecological engineering area were quantified.•The water conservation capacity notably increased from west to east during 2000–2015.•The water conserved increased in 66% of the study area and decreased in western area.•Rainfall, temperature, and vegetation determine the changes in water conservation.
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