Autonomous Self-Healing of Highly Stretchable Supercapacitors at All Climates.

Realizing autonomous self-healing and high stretchability of flexible supercapacitors over a wide temperature range remains a big challenge because of simultaneous incorporation of self-healing, stretchable and temperature-tolerant elements into a device as well as unfavorable electrochemical kinetics in harsh conditions. Here, we demonstrate for the first time an autonomous self-healing and intrinsically stretchable supercapacitor that can work at all-climate environments assembled by universally self-healing and highly stretchable organohydrogel electrodes with record-high temperature-invariant conductivity of ∼965 S/cm. Benefiting from multiple hydrogen bonding and dynamic metal coordination combined with electrochemistry-favorable components and integrated device configuration, the supercapacitor exhibits outstanding long-term stability, high stretchability, instantaneous and complete capacitive self-healability, and real-time mechanical healing at harsh temperatures from -35 to 80 °C. The superiorities in stretchability, self-healability, and all-climate tolerance enable the supercapacitor presented here as the best performer among the flexible supercapacitors reported to date.

[Temporal and spatial distribution of anthropogenic ammonia emissions in China: 1994-2006].

Ammonia has both direct and indirect impacts on important environmental issues including acid deposition, regional fine particles and eutrophication. Estimation of anthropogenic ammonia emissions will provide valuable information for the pollution control of acid deposition and regional fine particle. Based on the provincial activity data on N-fertilizer application, livestock farming, N-fertilizer production and populations, this paper uses emission factor method to estimate China's atmospheric ammonia emissions, analyzes its historical trends and presents its geographical distributions from year 1994 to 2006. The national total atmospheric ammonia emissions are estimated to be 11.06 million tons (Mt) in 1994, which increase quickly to 16.07 Mt in 2006. Emissions from livestock farming, N-fertilizer application, N-fertilizer production and human excreta have increased from 4.47 Mt, 5.94 Mt, 0.09 Mt, and 0.59 Mt in 1994 to 6.61 Mt, 8.68 Mt, 0.14 Mt, 0.65 Mt respectively in 2006. Livestock farming and N-fertilizer application are the most important ammonia emission sources, which contributed 40.79 and 55.53 percent of total emissions respectively in 2006. In 2006, the average ammonia emission intensity is 1.67 t x km(-2) but there are large variations among atmospheric ammonia emissions from each province. Emissions from provinces including Henan, Shandong, Hebei, Sichuan and Jiangsu accounted for 40.82 percent of national emissions.