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Ethanolamine solutions are a kind of important absorbent for carbon dioxide capture from flue gas. In this work, the absorption rate and absorption capacity of carbon dioxide by ethanolamine and piperazine solutions have been studied. Using a newly absorption equipment, the absorption rate was measured in monoethanolamine, diethanolamine and piperazine solutions with different concentration from 10 to 50 wt %, respectively. The experimental results showed that monoethanolamine and diethanolamine both have a large absorption rate and capacity. According to the experimental results and the zwitterion mechanism, the kinetics of the reaction between carbon dioxide and ethanolamine could be derived.

The trend towards efficient and intensive use of land resources is an inevitable outcome of current social development. The rational matching of urban land prices and land use intensity has become an important factor under accelerating urbanization, and promotes the healthy development of the social economy. Using data on residential land price and on land use intensity for 31 provinces and cities in China, we employ the E-G cointegration test and quadrant map classification to determine the coordination relationship between land price and land use intensity. We then employ HR coordination to calculate the coordination degree of land price and land use intensity, and classify the coordination type accordingly. Our results are as follows. (1) The spatio-temporal distribution of urban land price shows high variability with multiple maxima, and follows a decreasing trend from the southeast coastal area to the northwest inland area and the northeast. (2) The overall land use intensity is at or above the middle level, and shows large spatial differences between provinces, but the agglomeration between provinces is increasing. (3) From the perspective of the relationship between urban land price and land use intensity at the inter-provincial scale, we find that the land price and land use intensity are well coordinated, and the number of provinces has been dynamically changing during different development periods. There is an east-west difference in the spatial distribution of land price and land use intensity coordination level. Different provinces and cities with the same coordination stage show differences in their land price and land use intensity level.

In the context of the increasingly severe global carbon emission crisis, smoothly reducing emissions without affecting economic development and the continuous improvement of people’s living standards has become an important problem facing China, the country with the largest carbon emissions in the world. From the perspective of intensive land use (ILU), this paper uses standard deviational ellipse, decoupling theory, and a logarithmic mean Divisia index (LMDI) model to analyze the level of ILU and carbon emissions in 30 provinces, municipalities, and autonomous regions in China and explores ways to reduce emissions. The results show that: 1) The level of ILU in China’s 30 provinces (municipalities and autonomous regions) has shown steady progress and the overall carbon emissions from land use have shown a slow growth trend, but the carbon emissions of some provinces have shown a downward trend; 2) The ILU and the carbon emissions standard deviational ellipse have good spatial consistency, both of which have a north by east to south by west distribution pattern. The center of the carbon emission standard deviational ellipse moves to the northwest as a whole; 3) 63.33% of provinces are in the ideal decoupling stage of ILU and carbon emissions; 4) According to their contribution value, the influencing factors of China’s carbon emissions are, in descending order, energy intensity, economic scale, population scale, land use structure, energy carbon emission intensity, and land scale. Important directions for future efforts include actively adjusting the industrial structure and economic development mode, increasing the proportion of clean energy and energy utilization rate, controlling the speed of construction and land expansion, and promoting low-carbon emissions.

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