Price plays an important role in water resources management. The price of water resources can also be considered as a “water resource tax” which reflects the value and opportunity cost of water, and people will pay ...Price plays an important role in water resources management. The price of water resources can also be considered as a “water resource tax” which reflects the value and opportunity cost of water, and people will pay for the right to use water. Currently, the water resource fees’ effect of regulating resource differential revenues is not manifest and it’s not enough to reflect the principle of paid use of resources as well as regulating resources differential revenues. Due to the ambiguity and complexity of water resources price, this paper uses methods relating to fuzzy mathematics for modeling and processing. The study had a comprehensive consideration of five factors including water quality, water resources per capita, household consumption level, per capita GNP, population or population density to evaluate the water resource price.展开更多
Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 co...Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 coal samples were collected from Eastern Yunnan coal deposits,China,aiming to characterize the distribution and the occurrence of uranium in those coals.In studied samples,uranium content varied from 0.36 to 8.28 μg/g,with an average value of 3.76 lg/g.Generally,uranium content in coals from northern coal mines(3.02±2.44 μg/g,n=5)were lower than it in southern coal mines(4.13±2.30 μg/g,n=10).Uranium in coal samples showed no obvious correlation with total sulfur,whereas was positively correlated with ash yield.The results of sequential chemical extraction procedure confirm that organic-bound is the dominant occurrence of uranium.The slight enrichment of uranium in studied coals was probably attributed to sedimentation processes,hydrological conditions and tectonic structure of the coal deposits.展开更多
A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment...A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.展开更多
文摘Price plays an important role in water resources management. The price of water resources can also be considered as a “water resource tax” which reflects the value and opportunity cost of water, and people will pay for the right to use water. Currently, the water resource fees’ effect of regulating resource differential revenues is not manifest and it’s not enough to reflect the principle of paid use of resources as well as regulating resources differential revenues. Due to the ambiguity and complexity of water resources price, this paper uses methods relating to fuzzy mathematics for modeling and processing. The study had a comprehensive consideration of five factors including water quality, water resources per capita, household consumption level, per capita GNP, population or population density to evaluate the water resource price.
基金This work was supported by the National Basic Research Program of China(2014CB238903)the National Natural Science Foundation of China(41173032,41371444,41373110)+1 种基金the open project of Anhui Key Laboratory(ZYZWSW2014011)Anhui Provincial Department of Education University Scientific Research Project(KJ2020A1204).We acknowledge editors and reviewers for polishing the language of the paper and for in-depth discussion.
文摘Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 coal samples were collected from Eastern Yunnan coal deposits,China,aiming to characterize the distribution and the occurrence of uranium in those coals.In studied samples,uranium content varied from 0.36 to 8.28 μg/g,with an average value of 3.76 lg/g.Generally,uranium content in coals from northern coal mines(3.02±2.44 μg/g,n=5)were lower than it in southern coal mines(4.13±2.30 μg/g,n=10).Uranium in coal samples showed no obvious correlation with total sulfur,whereas was positively correlated with ash yield.The results of sequential chemical extraction procedure confirm that organic-bound is the dominant occurrence of uranium.The slight enrichment of uranium in studied coals was probably attributed to sedimentation processes,hydrological conditions and tectonic structure of the coal deposits.
基金supported by the National Basic Research Program of China (973 Program, 2014CB238903)the National Natural Science Foundation of China (Nos. 41672144, 41173032, and 41373110)
文摘A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.