Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions ...Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions (soil characteristics) and prevailing climate. The aims of the present study were to calculate carbon (C)--stock of biomass of 4 years old plantation (dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea), understorey vegetation and litter, soil organic carbon in reclaimed minesoil (RMS) and compare with reference forest site. Allometric equation was used for the estimation of biomass C stock and found 13.0 Mg C ha i (A lebbeck 7.8 Mg C ha-I, D sissoo 3.5 Mg C ha-l and B. arundincea 1.2 Mg C ha-l), while stock of understorey vegetation was 0.98 Mg C ha-~. In RMS, C stock was 16.3 Mg C ha-1, out of which inorganic C contributed 1.7 g kg-l (8 % of total soil C), Coal C 8.7 g kg^-1 (43 % of total soil C) and biogenic C 9.8 g kg^-1 (49 % of total soil C). Total C stock in reclaimed site was calculated as 30.3 Mg C ha^-1(equivalent to 111 Mg CO2 ha-b. The study concluded that (i) coal C is responsible for overestimation of C stock in RMS (ii) Maximun C stock stored in aboveground biomass component and (iii) reclaimed mined lands will take approximately 17 years to reach the level of C stock of reference forest site in dry tropical climate.展开更多
Chinese fir is one of the largest distributions of commercial forest plantation in South China. In this study, we chose the different regeneration patterns of Chinese fir for our researches, the results showed differe...Chinese fir is one of the largest distributions of commercial forest plantation in South China. In this study, we chose the different regeneration patterns of Chinese fir for our researches, the results showed different regeneration patterns affected both the quantity and quality of soil organic carbon. clear cutting followed by different regeneration in old-growth Chinese fir decreased the quantity of soil organic carbon both in artificial regeneration forest and natural regeneration forest, and both of them were significantly different with the old-growth Chinese fir forest (p〈0.05). The concentrations of soil organic carbon(SOC) and particulate organic carbon(POC) in natural regeneration forest were higher than those in artificial regeneration forest, and the difference was significant in the 0-5 cm layer (p〈0.05). Different regeneration patterns decreased forest SOC storage. Compared with the old-growth Chinese fir, SOC storage in 0-100 cm layer decreased by 7.09% and 13.27% in natural regeneration forest and artificial regeneration forest respectively, and the differences were both significant (p〈0.05). In addition, SOC storage in 0-100 cm layer of natural regeneration forest was 7.13% higher than that in artificial regeneration forest.展开更多
基于建筑垃圾的综合处置技术,制备出无机再生粉、有机再生粉和混合再生粉,并利用其取代水泥(质量取代分数:12.5%、25%、37.5%、50%)制备超高性能混凝土(Ultra high performance concrete, UHPC)。结果表明:无机再生粉和混合再生粉取代...基于建筑垃圾的综合处置技术,制备出无机再生粉、有机再生粉和混合再生粉,并利用其取代水泥(质量取代分数:12.5%、25%、37.5%、50%)制备超高性能混凝土(Ultra high performance concrete, UHPC)。结果表明:无机再生粉和混合再生粉取代水泥总体上会降低UHPC基体的工作性能和抗压强度,但使用25%的无机再生粉和混合再生粉取代水泥制备的UHPC基体28 d抗压强度几乎没有下降;有机再生粉取代水泥可以提高UHPC的工作性能,但是其制备的UHPC抗压强度下降明显。有机再生粉取代量12.5%时制备的UHPC性能在使用接受范围内。可见合理利用建筑垃圾再生料可以生产出性能优异的生态型超高性能混凝土。展开更多
Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly coval...Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.展开更多
An improved acetylcholinesterase liquid crystal(LC) biosensor has been developed for the identification of organophosphates(OPs) by using a reactivator. When the acetylcholinesterases(AChEs) inhibited by different kin...An improved acetylcholinesterase liquid crystal(LC) biosensor has been developed for the identification of organophosphates(OPs) by using a reactivator. When the acetylcholinesterases(AChEs) inhibited by different kinds of OPs are reactived by a reactivator, the catalytic activity of AChEs can be recovered with different activation efficiency because of the different phosphorylation structures formed in the inhibited AChEs. Accordingly, the reactived AChEs can catalyze the hydrolysis of acetylthiocholine to generate thiocholine product in different degrees, which will result in different catalytic growth of AuNPs and further form distinct orientational response of LCs. Based on such a reactivation mechanism, the AChE LC biosensor with a simple, rapid and visual procedure achieves an obvious identification of three OPs pesticides, methamidophos, trichlorfon and paraoxon, by using a pralidoxime reactivator.展开更多
Recently,crystalline porous materials such as metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)have attracted much interest not only in chemistry but also in materials science due to their tunabl...Recently,crystalline porous materials such as metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)have attracted much interest not only in chemistry but also in materials science due to their tunable structures and functional channels.They have some inherent disadvantages of being difficult to solution process and recovery,which might limit their wide usage.展开更多
文摘Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions (soil characteristics) and prevailing climate. The aims of the present study were to calculate carbon (C)--stock of biomass of 4 years old plantation (dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea), understorey vegetation and litter, soil organic carbon in reclaimed minesoil (RMS) and compare with reference forest site. Allometric equation was used for the estimation of biomass C stock and found 13.0 Mg C ha i (A lebbeck 7.8 Mg C ha-I, D sissoo 3.5 Mg C ha-l and B. arundincea 1.2 Mg C ha-l), while stock of understorey vegetation was 0.98 Mg C ha-~. In RMS, C stock was 16.3 Mg C ha-1, out of which inorganic C contributed 1.7 g kg-l (8 % of total soil C), Coal C 8.7 g kg^-1 (43 % of total soil C) and biogenic C 9.8 g kg^-1 (49 % of total soil C). Total C stock in reclaimed site was calculated as 30.3 Mg C ha^-1(equivalent to 111 Mg CO2 ha-b. The study concluded that (i) coal C is responsible for overestimation of C stock in RMS (ii) Maximun C stock stored in aboveground biomass component and (iii) reclaimed mined lands will take approximately 17 years to reach the level of C stock of reference forest site in dry tropical climate.
基金Acknowledgements: This work is supported by National Natural Science Foundation of China (No. 30571488) and Natural Science Foundation of Fujian (No. 2007J0121). The School of Geographical Science, Fujian Normal University is also thanked.
文摘Chinese fir is one of the largest distributions of commercial forest plantation in South China. In this study, we chose the different regeneration patterns of Chinese fir for our researches, the results showed different regeneration patterns affected both the quantity and quality of soil organic carbon. clear cutting followed by different regeneration in old-growth Chinese fir decreased the quantity of soil organic carbon both in artificial regeneration forest and natural regeneration forest, and both of them were significantly different with the old-growth Chinese fir forest (p〈0.05). The concentrations of soil organic carbon(SOC) and particulate organic carbon(POC) in natural regeneration forest were higher than those in artificial regeneration forest, and the difference was significant in the 0-5 cm layer (p〈0.05). Different regeneration patterns decreased forest SOC storage. Compared with the old-growth Chinese fir, SOC storage in 0-100 cm layer decreased by 7.09% and 13.27% in natural regeneration forest and artificial regeneration forest respectively, and the differences were both significant (p〈0.05). In addition, SOC storage in 0-100 cm layer of natural regeneration forest was 7.13% higher than that in artificial regeneration forest.
基金financial support of the National Natural Science Foundation of China (20876055, 21076085)the Natural Science Foundation of Guangdong Province (S2011020001472)the Fundamental Research Funds for the Central Universities, SCUT
文摘Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.
基金supported by the International Scientific and Technological Cooperation Projects of China(2012DFR40480)the National Natural Science Foundation of China(21175037,21277042 and J1210040)
文摘An improved acetylcholinesterase liquid crystal(LC) biosensor has been developed for the identification of organophosphates(OPs) by using a reactivator. When the acetylcholinesterases(AChEs) inhibited by different kinds of OPs are reactived by a reactivator, the catalytic activity of AChEs can be recovered with different activation efficiency because of the different phosphorylation structures formed in the inhibited AChEs. Accordingly, the reactived AChEs can catalyze the hydrolysis of acetylthiocholine to generate thiocholine product in different degrees, which will result in different catalytic growth of AuNPs and further form distinct orientational response of LCs. Based on such a reactivation mechanism, the AChE LC biosensor with a simple, rapid and visual procedure achieves an obvious identification of three OPs pesticides, methamidophos, trichlorfon and paraoxon, by using a pralidoxime reactivator.
文摘Recently,crystalline porous materials such as metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)have attracted much interest not only in chemistry but also in materials science due to their tunable structures and functional channels.They have some inherent disadvantages of being difficult to solution process and recovery,which might limit their wide usage.