The role of Nil(NO3)2 in the preparation of a magnetic activated carbon is reported in this paper. Magnetic coal-based activated carbons (MCAC) were prepared from Taixi anthracite with low ash content in the prese...The role of Nil(NO3)2 in the preparation of a magnetic activated carbon is reported in this paper. Magnetic coal-based activated carbons (MCAC) were prepared from Taixi anthracite with low ash content in the presence of Ni(NO3)2. The MCAC materials were characterized by a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), a scanning electric microscope (SEM), and by N2 adsorption. The cylindri- cal precursors and derived char were also subjected to thermogravimetric analysis to compare their behavior of weight losses during carbonization. The results show that MCAC has a larger surface area (1074 m21g) and a higher pore volume (0.5792 cm3/g) with enhanced mesopore ratio (by about 10~). It also has a high saturation magnetization (1.6749 emu/g) and low coercivity (43.26 Oe), which allows the material to be magnetically separated. The MCAC is easily magnetized because the nickel salt is con- vetted into Ni during carbonization and activation. Metallic Ni has a strong magnetism on account of electrostatic interaction. Added Ni(NO3)2 catalyzes the carbonization and activation process by accelerat- ing burn off of the carbon, which contributes to the development of mesopores and macropores in the activated carbon.展开更多
Land use, land-use change and forestry (LULUCF) activities can allow Annex I parties in the Kyoto Protocol to decrease their carbon emission reduction pressure, and comparably expanding more emission space for their...Land use, land-use change and forestry (LULUCF) activities can allow Annex I parties in the Kyoto Protocol to decrease their carbon emission reduction pressure, and comparably expanding more emission space for their domestic industries and energy production. The loopholes resulted from LULUCF activity types and specific accounting methods are always argued among the different parties, particularly including harvested wood products, influences of force majeure, threshold values of the reference level, and gross-net or net-net accounting methods. For estimating uncertainties in accounting loopholes, and to avoid that developed countries take advantage of the account{ng loopholes of LULUCF to decrease their emission reduction pressure, the LULUCF data submitted from the main developed countries in Annex I, including EU 27, Canada, Japan, and Russia, were collected. According to the analysis of these data, the loopholes influence the accounting results of LULUCF. The results show that the uncertainty of harvested wood products is excessive. The carbon sink produced by LULUCF activities will increase averagely by at least 30% without force majeure. The threshold values of the reference level of carbon sink should be set to a higher level. The net-net accounting method might be more suitable for LULUCF after 2012.展开更多
基金support by the National Natural Science Foundation of China (No. 20776150)the National Hi-Tech Research and Development Program of China(No. 2008AA05Z308)the Special Fund for Basic Scientific Research of Central Colleges (No. 2009QH15)
文摘The role of Nil(NO3)2 in the preparation of a magnetic activated carbon is reported in this paper. Magnetic coal-based activated carbons (MCAC) were prepared from Taixi anthracite with low ash content in the presence of Ni(NO3)2. The MCAC materials were characterized by a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), a scanning electric microscope (SEM), and by N2 adsorption. The cylindri- cal precursors and derived char were also subjected to thermogravimetric analysis to compare their behavior of weight losses during carbonization. The results show that MCAC has a larger surface area (1074 m21g) and a higher pore volume (0.5792 cm3/g) with enhanced mesopore ratio (by about 10~). It also has a high saturation magnetization (1.6749 emu/g) and low coercivity (43.26 Oe), which allows the material to be magnetically separated. The MCAC is easily magnetized because the nickel salt is con- vetted into Ni during carbonization and activation. Metallic Ni has a strong magnetism on account of electrostatic interaction. Added Ni(NO3)2 catalyzes the carbonization and activation process by accelerat- ing burn off of the carbon, which contributes to the development of mesopores and macropores in the activated carbon.
基金supported by China "973" projects of Special Negotiating Problems for LULUCF Response to Climate Change(No2010CB955702)Space-time Pattern of Carbon and Nitrogen and Water Flux of Chinese Terrestrial Ecosystem and its Regional Response(No 2010CB833504)
文摘Land use, land-use change and forestry (LULUCF) activities can allow Annex I parties in the Kyoto Protocol to decrease their carbon emission reduction pressure, and comparably expanding more emission space for their domestic industries and energy production. The loopholes resulted from LULUCF activity types and specific accounting methods are always argued among the different parties, particularly including harvested wood products, influences of force majeure, threshold values of the reference level, and gross-net or net-net accounting methods. For estimating uncertainties in accounting loopholes, and to avoid that developed countries take advantage of the account{ng loopholes of LULUCF to decrease their emission reduction pressure, the LULUCF data submitted from the main developed countries in Annex I, including EU 27, Canada, Japan, and Russia, were collected. According to the analysis of these data, the loopholes influence the accounting results of LULUCF. The results show that the uncertainty of harvested wood products is excessive. The carbon sink produced by LULUCF activities will increase averagely by at least 30% without force majeure. The threshold values of the reference level of carbon sink should be set to a higher level. The net-net accounting method might be more suitable for LULUCF after 2012.