The addition of municipal solid wastes （MSW） is considered as a possible strategy for soil rehabilitation in southeast Spain. The objective of this study was to evaluate the long-term （17 years） effect of five dos...The addition of municipal solid wastes （MSW） is considered as a possible strategy for soil rehabilitation in southeast Spain. The objective of this study was to evaluate the long-term （17 years） effect of five doses of MSW addition on the microbiological, biochemical, and physical properties of semiarid soil. Increased values of several parameters that serve as indicators of general microbiological activity, such as, basal respiration, adenosine triphosphate （ATP） or dehydrogenase activity; microbial population size （microbial biomass C）, and extracellular hydrolase activity related to macronutrient cycles, such as, urease, 3-glucosidase, and N-a-benzoyl-L-argininamide protease, were observed in the amended soils. The highest MSW doses showed the highest values in these hydrolase activities. The incorporation of municipal waste resulted in a more dense development of the plant cover, 50% greater in higher doses than in the control treatment, which generated a substantial increase in several C fractions. Total organic carbon reached 12 g kg^-1 soil with the highest MSW doses, compared to 4.30 g kg^-1 soil in the control treatment. The physical properties of the soil were also improved, showing greater percentage of stable aggregates and water holding capacity. Positive correlation coefficients between C fractions and parameters related to microbial activity and aggregate stability were observed. Although these improvements were greater in the soils receiving the highest doses of organic amendment, the increases were not proportional to the amount added, demonstrating the existence of a threshold, above which an increase in the amount of organic matter added is not reflected in an increase in the soil＇s physical, biochemical, and microbiological properties. However, the addition of municipal solid wastes proved its suitability for improving soil quality, thereby indicating the potential of such an amendment, to prevent desertification in Mediterranean areas such as those studied.展开更多
Sulfur(S)-doped graphene sheets were prepared by a facile electrochemical method, which effectively combined exfoliation of graphite and in situ S doping of graphene together. The metal-free S-doped graphene sheets ex...Sulfur(S)-doped graphene sheets were prepared by a facile electrochemical method, which effectively combined exfoliation of graphite and in situ S doping of graphene together. The metal-free S-doped graphene sheets exhibit high electrocatalytic activity, long-term stability, and excellent tolerance to cross-over effects of methanol in alkaline media for the oxygen reduction reaction(ORR), indicating that these S-doped graphene sheets possess great potential for a substitute for Pt-based catalysts in fuel cells.展开更多
基金Project supported by the EU and the Spanish Ministry of Science and Technology.
文摘The addition of municipal solid wastes （MSW） is considered as a possible strategy for soil rehabilitation in southeast Spain. The objective of this study was to evaluate the long-term （17 years） effect of five doses of MSW addition on the microbiological, biochemical, and physical properties of semiarid soil. Increased values of several parameters that serve as indicators of general microbiological activity, such as, basal respiration, adenosine triphosphate （ATP） or dehydrogenase activity; microbial population size （microbial biomass C）, and extracellular hydrolase activity related to macronutrient cycles, such as, urease, 3-glucosidase, and N-a-benzoyl-L-argininamide protease, were observed in the amended soils. The highest MSW doses showed the highest values in these hydrolase activities. The incorporation of municipal waste resulted in a more dense development of the plant cover, 50% greater in higher doses than in the control treatment, which generated a substantial increase in several C fractions. Total organic carbon reached 12 g kg^-1 soil with the highest MSW doses, compared to 4.30 g kg^-1 soil in the control treatment. The physical properties of the soil were also improved, showing greater percentage of stable aggregates and water holding capacity. Positive correlation coefficients between C fractions and parameters related to microbial activity and aggregate stability were observed. Although these improvements were greater in the soils receiving the highest doses of organic amendment, the increases were not proportional to the amount added, demonstrating the existence of a threshold, above which an increase in the amount of organic matter added is not reflected in an increase in the soil＇s physical, biochemical, and microbiological properties. However, the addition of municipal solid wastes proved its suitability for improving soil quality, thereby indicating the potential of such an amendment, to prevent desertification in Mediterranean areas such as those studied.
基金supported by the National Natural Science Foundation of China(21073018)the Major Research Plan of the National Natural Science Foundation of China(21233003)the Fundamental Research Funds for the Central Universities,Key Laboratory of Theoretical and Computational Photochemistry
文摘Sulfur(S)-doped graphene sheets were prepared by a facile electrochemical method, which effectively combined exfoliation of graphite and in situ S doping of graphene together. The metal-free S-doped graphene sheets exhibit high electrocatalytic activity, long-term stability, and excellent tolerance to cross-over effects of methanol in alkaline media for the oxygen reduction reaction(ORR), indicating that these S-doped graphene sheets possess great potential for a substitute for Pt-based catalysts in fuel cells.
