The political environment of the South China Sea Region(SCSR)has gradually stabilized,such that regional cooperation in the preservation of marine resources seems realistic.Blue carbon international cooperation is an ...The political environment of the South China Sea Region(SCSR)has gradually stabilized,such that regional cooperation in the preservation of marine resources seems realistic.Blue carbon international cooperation is an important solution to the problem of global warming,which has a large number of economic and political attributes.As a region that has incredibly abundant blue carbon resources,further cooperation among SCSR governments would present the opportunity to establish meaningful economic and environmental protections that would promote peaceful blue carbon development of this region.To examine the feasibility of such an undertaking,we leverage the imitator's dynamic game as a research method and introduce Weber's law to examine the subjective psychological factors(i.e.,biases)of participants in qualifying the economic stability of blue carbon cooperation in the SCSR.The results suggest that the economic stability of blue carbon cooperation correlates to Weber's coefficient and the income produced by the different strategies.Based on these findings,we discussed policy recommendations to promote the sustainable economic development of SCSR.展开更多
Environmental protection has become a concern for the world. For this reason, the objective of this work is to remove methylene blue adsorbed on activated carbon. The coal used comes from cocoa pod shells. Before pyro...Environmental protection has become a concern for the world. For this reason, the objective of this work is to remove methylene blue adsorbed on activated carbon. The coal used comes from cocoa pod shells. Before pyrolysis, the shells were ground, sieved and impregnated with orthophosphoric acid. Before desorption, the activated carbons were initially saturated with MB. These saturated coals were brought into contact with a sodium chloride (NaCl) solution and then stirred. The evolution of the resorbed MB concentration was monitored by spectrophotometry. The desorption tests showed a remarkable elimination from the first 10 minutes. The desorption kinetics comprises two phases: a rapid kinetics between 0 and 30 minutes and a slow kinetics between 30 and 60 minutes. The desorption of the dye reaches a concentration aqual to 0.84 mg/l at pH = 4 at temperature = 80°C. For modeling, the coefficient of the Langmuir II model is greater than or equal to O.9893. The model of Langmuir III is less than or equal to 0.9373. The Freundlich model coefficient is 0.9842 or less. The desorption is thefore carried out on energy-homogeneous adsorption sites and without any interaction between the adsorbed cations of the dye. Experimental parameters such as pH, temperature and concentration of sodium chloride (NaCl) solution influence the desorption of MB. And the model of Langmuir II describes well the process of desorption of the MB.展开更多
This research investigates the efficacy of activated Gmelina Wood Sawdust (GWS) as an adsorbent for the removal of methylene blue (MB) dye from aqueous solutions, in comparison with raw GWS. The study employs laborato...This research investigates the efficacy of activated Gmelina Wood Sawdust (GWS) as an adsorbent for the removal of methylene blue (MB) dye from aqueous solutions, in comparison with raw GWS. The study employs laboratory experiments to assess the percentage of dye removal across various temperature and pH conditions. The adsorption process is scrutinized under different parameters, encompassing contact time, initial dye concentration, adsorbent dosage, temperature, and pH. Results demonstrate that activated GWS surpasses its raw counterpart, showcasing superior MB dye removal percentages. Extended contact times increased initial dye concentrations, and higher adsorbent dosages contribute positively to removal efficiency, while temperature exhibits an inverse relationship with dye removal. Optimal adsorption occurs at a pH of 7.0, aligning with the adsorbent’s zero-point charge (pHzpc), underscoring the role of surface charge in the adsorption process. This study underscores the potential of activated GWS as an economical and promising adsorbent material for addressing pollutants. Furthermore, the utilization of activated carbon derived from abundant agricultural waste underscores an environmentally conscious approach to adsorption applications. The ability to tailor the size and properties of activated carbon particles opens avenues for optimizing adsorption capabilities, thereby presenting opportunities for enhanced water treatment solutions.展开更多
Introduction:Large stocks of“blue carbon”exist in the ecosystems of coastal wetlands.This paper presents a case study of the Chinese city of Yancheng.First,through field surveys and laboratory analysis,changes in th...Introduction:Large stocks of“blue carbon”exist in the ecosystems of coastal wetlands.This paper presents a case study of the Chinese city of Yancheng.First,through field surveys and laboratory analysis,changes in the organic carbon(OC)content in typical plant communities throughout the study area are described in detail.Second,an OC burial rate and economic value model is constructed to analyze the composition of the carbon sink values.Outcomes/other:The results are as follows:Of the typical plant communities,Spartina alterniflora has the highest OC content(5.80 g·kg-1),followed by Suaeda glauca(4.78 g·kg-1)and Phragmites australis(3.76 g·kg-1);the contemporary OC sedimentation rates are 2.01,1.48,and 1.22 cm·yr-1,respectively.Spartina alterniflora communities have the highest annual average carbon sink value($418.74/ha)in the study area,followed by Phragmites australis($176.29/ha)and Suaeda glauca($101.54/ha).Discussion:As a result of both the expansion of the Spartina alterniflora area and coastal erosion,the total OC value since 1987 has displayed two-stage characteristics:it first increased and then decreased.Conclusion:In recent years,the annual average decline in OC value has ranged from approximately$82,100 to$123,100(reference:the Sweden carbon tax provided by the World Bank,130$/ton)展开更多
Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plant...Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plants and microbes; and stored in nearshore sediments and soils; as well as the carbon transported from the coast to the ocean and ocean floor. The carbon sequestration capacity per unit area of coastal blue carbon is far greater than that of the terrestrial carbon pool. The mechanisms and controls of the carbon sink from salt marshes, mangroves, seagrasses, the aquaculture of shellfish and macroalgae, and the microbial carbon pump need to be further studied. The methods to quantify coastal blue carbon include carbon flux measurements, carbon pool measurements, manipulative experiments, and modeling. Restoring, conserving, and enhancing blue carbon will increase carbon sinks and produce carbon credits, which could be traded on the carbon market. The need to tackle climate change and implement China's commitment to cut carbon emissions requires us to improve studies on coastal blue carbon science and policy. The knowledge learned from coastal blue carbon improves the conservation and restoration of salt marshes,mangroves, and seagrasses; enhances the function of the microbial carbon pump; and promotes sustainable aquaculture, such as ocean ranching.展开更多
Sequestration of blue carbon(C)in mangrove plantations depends on site characteristics and plantation management.This study evaluated the effects of plantation management on C sequestration at a C-neutral site in Xiam...Sequestration of blue carbon(C)in mangrove plantations depends on site characteristics and plantation management.This study evaluated the effects of plantation management on C sequestration at a C-neutral site in Xiamen,China.A field study was conducted on 10-year-old Sonneratia apetala and Kandelia obovata plantations(mono-Sa,mono-Ko)and a 15-year-old mixed plantation-.We found that mono-Ko had a significantly higher ecosystem C sequestration rate(3.32±0.62 kg C m^(-2)yr^(-1))than others when planted in the indirect shade of pioneer species.As a non-native species,Sonneratia performed better(0.57±0.01 kg C m^(-2)yr^(-1))when planted with Kandelia than in monotypic plantations.The temporary and long-term certified emission reduction(tCER and lCER)of the 12.98 ha mono-Ko was 4103.89 and 3693.50 net CO_(2)-e within 10 years,respectively.A literature review was conducted to show the compatibility of this study with other natural and plantation sites of China and Bangladesh(the native habitat for Sonneratia).The C sequestration of Sonneratia plantation sites in China is comparable with those in Bangladesh.However,the soil C accumulation rate for a Sonneratia monotypic plantation in Bangladesh decreased with age,yet the same did not occur in the plantations of China.展开更多
This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),wher...This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),where some pools as seagrasses,and salt marshes,are highly efficient at capturing and storing carbon dioxide(CO_(2))from the atmosphere.Halophyte salt marsh plants were found to have a%C on Dry Weight(D.W.)of 32.26±3.91(mean±standard deviation),macrophytes 33.65±7.99,seagrasses 29.23±2.23,tamarisk 48.42±2.80,while the first 5 centimetres of wetland mud,on average,had a%C of 8.56±0.94.Like the ISO(International Organization for Standardization)14064 guideline to quantify the GHG(Greenhouse Gas)emission,we have studied the different conversion factors to be used as a practical tool for measurement the CO_(2)sink activity.These factors are essential to calculate the overall carbon reduction in a project located in temperate wetland using a method as the ISO 14064.2,UNI-BNeutral,VCS VERRA or other that will come.展开更多
Hierarchically interconnected porous activated carbon have high specific surface areas, large numbers of dye adsorption sites, and interconnected pores for dye molecule diffusion and transportation. We prepared hierar...Hierarchically interconnected porous activated carbon have high specific surface areas, large numbers of dye adsorption sites, and interconnected pores for dye molecule diffusion and transportation. We prepared hierarchically interconnected porous banana peel activated carbons(BPACs) via a green method involving hydrothermal pretreatment and KOH activation, and systematically tested its methylene blue(MB) adsorption capacity. SEM showed that the BPACs had an interconnected porous structure and high-porosity surface. The Brunauer-Emmett-Teller surface area was 601.21 m^2/g, the adsorption average pore diameter was 2.11 nm, and the total pore volume was 0.32 cm^3/g. The MB adsorption capacity increased with increasing temperature, initial MB concentration, and pH value; it decreased with increasing adsorbent dosage. The adsorption isotherms and kinetic results for MB adsorption on BPACs were best described by the Langmuir adsorption and pseudo-second-order kinetic models, respectively. BPACs have a well-developed hierarchically interconnected porous structure, which increase the MB adsorption capacity and removal efficiency. Systematic MB adsorption tests show that BPAC is a highly efficient and easily available adsorbent.展开更多
An attempt was made to prepare carbon coated tourmaline by mixing tourmaline powders and polyvinyl alcohol (PVA), followed by heat treatment in argon atmosphere. All samples were characterized by powder X-ray diffract...An attempt was made to prepare carbon coated tourmaline by mixing tourmaline powders and polyvinyl alcohol (PVA), followed by heat treatment in argon atmosphere. All samples were characterized by powder X-ray diffraction, high-resolution transmission electron microscopy, UV diffuse reflectance spectroscopy. Results showed that the residual carbon content was influenced by heat treatment temperature and the amount of PVA. The degradation of methylene blue by Carbon-coated tourmaline was also studied. The experiments pointed out that the carbon coated effects are best when the heating temperature was 900℃ and the weight content of PVA was 70%. And the tourmaline prepared under 900℃ in the oxidation atmosphere has the best degrade efficiency. The results also proved that the infrared radiation of tourmaline is not effect in the degrade progress.展开更多
A batch fixed bed photoreactor,using felt-form activated carbon fibers(ACF)supported TiO2 photocatalyst(TiO2/ACF),was developed to carry out photocatalytic degradation of methylene blue(MB)solution.The effects of TiO2...A batch fixed bed photoreactor,using felt-form activated carbon fibers(ACF)supported TiO2 photocatalyst(TiO2/ACF),was developed to carry out photocatalytic degradation of methylene blue(MB)solution.The effects of TiO2 particle size,loaded TiO2 amount,initial MB concentration,airflow rate and successive run on the decomposition rate were investigated.The results showed that photodegradation process followed a pseudo-first-order reaction kinetic law.The apparent first-order reaction constant kapp was larger than 0.047 min- 1 with half reaction time t1/2 shorter than 15 min,which was comparable to reported data using suspended Degussa P-25 TiO2 particles.The high degradation rate was mainly attributed to adsorption of MB molecules onto the surface of TiO2/ACF.The photocatalytic efficiency still remained nearly 90%after 12 successive runs,showing that successive usage of the designed photoreactor was possible.The synergic enhancement effect in combination of adsorption with ACF and photodegradation with TiO2 was proved by comparing MB removal rates in the successive degradation and adsorption runs,respectively.展开更多
The effects of O<sub>2</sub> plasma treatment on the adsorption capacity of activated carbon (AC) were investigated by varying the plasma treatment times. The surface properties of the AC were characterize...The effects of O<sub>2</sub> plasma treatment on the adsorption capacity of activated carbon (AC) were investigated by varying the plasma treatment times. The surface properties of the AC were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Zeta potential. The carbon was then applied to remove methylene blue (MB). The adsorption kinetics and isotherm were also studied. Results showed that pseudo-second-order kinetics was the most suitable model for describing the adsorption of MB onto AC. Equilibrium data were well fitted to the Freundlich isotherm model. The highest adsorption capacity resulted from 4 minutes of O2 plasma treatment. The 4-minute plasma treated AC had the best adsorption capacity for MB at 0.467 mg/mg. This work shows that activation of AC by plasma can open the micropore and increase the effectiveness of chemical removal.展开更多
A novel electrochemical method for the determination of sulphide at a multi-walled carbon nanotube-dihexadecyl hydrogen phosphate composite film coated glassy carbon electrode （MWNTs-DHP/GCE） based on in situ synthe...A novel electrochemical method for the determination of sulphide at a multi-walled carbon nanotube-dihexadecyl hydrogen phosphate composite film coated glassy carbon electrode （MWNTs-DHP/GCE） based on in situ synthesis of methylene blue （MB） was established. 2007 Sheng Shui Hu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Photodegradation of methylene blue (MB) and phenol (Ph) on TiO2 in presence of H-type and L-type activated carbons (AC) was studied. Photodegradation of MB and Ph were studied under two different lamps and results wer...Photodegradation of methylene blue (MB) and phenol (Ph) on TiO2 in presence of H-type and L-type activated carbons (AC) was studied. Photodegradation of MB and Ph were studied under two different lamps and results were compared against those obtained on a commercial TiO2. Apparent first order rate constant for the degradation of MB was higher in presence of any AC in comparison of TiO2 alone while only in presence of ACco2-800phenol was photodegradated in shorter irradiation time than that required by TiO2. It can be concluded that TiO2 enhances its photoactivity by a factor up to 8.7 in the degradation of MB in presence of AC and this effect is associated to the specific surface properties of AC.展开更多
The present study aims to develop effective adsorption and oxidation of synthetic dye in wastewater by using the newly synthesized iron-amended activated carbon. Recently synthetic dye-containing wastewater has gained...The present study aims to develop effective adsorption and oxidation of synthetic dye in wastewater by using the newly synthesized iron-amended activated carbon. Recently synthetic dye-containing wastewater has gained more attention due to its mass discharge, high toxicity and low biodegradation. For enhancing adsorption of dye and oxidative regeneration of dye-exhausted activated carbon, the novel amendment of iron-deposited granular activated carbon (GAC) was developed. It was to amend ferrous ion onto the acid-pretreated GAC when pH of iron solution was higher than the pH at point of zero charge (pH, pzc) of the GAC. Methylene blue (MB) in water was adsorbed onto the acid-treated iron- amended GAC (Fe-GAC) followed by single or multiple applications of H2O2. Batch experiments were carried out to study the adsorption isotherm and kinetics indicating adsorption of MB onto the Fe-GAC followed Langmuir isotherm and the pseudo-second order kinetics. The Fe-GACshowed the maximum adsorption capacity (qm) of 238.1 ± 0.78 mg/g which was higher than the virgin GAC with qm of 175.4 ± 13.6 mg/g at 20?C, pH 6 and the initial concentration of 20 - 200 mg/L. The heterogeneous Fenton oxidation of MB in the Fe-GAC revealedthat increasing the H2O2 loading from 7 to 140 mmol H2O2/mmol MB led to enhancing the oxidation efficiency of MB in the GAC from 62.6% to 100% due to the increased generation of hydroxyl radicals. Further enhancement of oxidation of MB in the Fe-GAC was made by the multiple application of H2O2 while minimizing OH radical scavenging often occurring at high concentration of H2O2. Therefore, the acid-treated iron-amended GAC would provide excellent adsorption capacity for MB and high oxidation efficiency of MB in the GAC with multiple applications of H2O2 and optimum iron loading.展开更多
Porous carbons are extensively applied in gas separation, water purification, catalytic reaction, and electrochemical processing, attributing to their high specific surface area, large pore volume, chemical inertness,...Porous carbons are extensively applied in gas separation, water purification, catalytic reaction, and electrochemical processing, attributing to their high specific surface area, large pore volume, chemical inertness, and good mechanical and thermal stability. The templating method is widely used to synthesize porous carbons with the controlled pore structure. Among them, preparation of diatomite-templated carbons attracts increasing attention because the obtained carbon has unique developed macropores and exhibits the promising application in adsorption and support of large-sized molecules. Macroporous diatomite-templated carbons are prepared by using additive or inherent solid acid sites of diatomite as the catalyst. The obtained carbons showed tubular and pillared macroporous structures, and had a few mesopores and micropores. However, the carbons possessed the small specific surface area and micropore volume, and thus showed the low adsorption capacity of small-sized molecules, such as methylene blue (MB). In this case, enhancement of porosity, especially microporosity, is necessary.展开更多
The adsorption capacity of steam activated carbon prepared from Delonix regia pods SADRC for adsorption of Aniline Blue (AB) from aqueous solution was investigated under various experimental conditions. Batch study wa...The adsorption capacity of steam activated carbon prepared from Delonix regia pods SADRC for adsorption of Aniline Blue (AB) from aqueous solution was investigated under various experimental conditions. Batch study was conducted to assess the potential of the activated carbon for the removal of Aniline Blue from aqueous solution. Activated carbon prepared from Delonix regia pods was characterized using Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FTIR) Spectrophotometry before and after adsorption. The FTIR, spectra of SADRC pod before and after Aniline Blue adsorption were compared to study the impact of the Aniline Blue on the activated carbon developed from the Delonix regia pod. The stretching vibration band at 2169.54 cm-1 may be due to strong CN, while the stretching vibration band at around 1580 - 1650 cm-1 may be due to C=C stretching vibration. The bands around 1350 and 426.49 cm-1 are due to C-N and –SO3H group, respectively;this further suggests that some functional groups may be present on the surface of the carbon due to the low temperature of carbonization (300°C) of the adsorbent. Equilibrium isotherm studies were carried out by varying the following four parameters: initial concentration of Aniline Blue dye solution, solution pH and adsorbent dose. The equilibrium data obtained were more fitted to Langmuir than Freundlich isotherm models. The correlation coefficient value (R2) of the pseudo first order kinetics ranged from 0.08 to 0.85 while the R2 of the pseudo second order kinetics ranged from 0.963 to 0.997 at all the temperatures and initial concentrations considered. This suggests that the adsorption kinetics of Aniline Blue onto SADRC can be represented with pseudo second order kinetic model. This study showed that Delonix regia pod could be effectively used as an adsorbent for the removal of Aniline Blue from aqueous solutions over a wide range of concentration and temperature.展开更多
文摘The political environment of the South China Sea Region(SCSR)has gradually stabilized,such that regional cooperation in the preservation of marine resources seems realistic.Blue carbon international cooperation is an important solution to the problem of global warming,which has a large number of economic and political attributes.As a region that has incredibly abundant blue carbon resources,further cooperation among SCSR governments would present the opportunity to establish meaningful economic and environmental protections that would promote peaceful blue carbon development of this region.To examine the feasibility of such an undertaking,we leverage the imitator's dynamic game as a research method and introduce Weber's law to examine the subjective psychological factors(i.e.,biases)of participants in qualifying the economic stability of blue carbon cooperation in the SCSR.The results suggest that the economic stability of blue carbon cooperation correlates to Weber's coefficient and the income produced by the different strategies.Based on these findings,we discussed policy recommendations to promote the sustainable economic development of SCSR.
文摘Environmental protection has become a concern for the world. For this reason, the objective of this work is to remove methylene blue adsorbed on activated carbon. The coal used comes from cocoa pod shells. Before pyrolysis, the shells were ground, sieved and impregnated with orthophosphoric acid. Before desorption, the activated carbons were initially saturated with MB. These saturated coals were brought into contact with a sodium chloride (NaCl) solution and then stirred. The evolution of the resorbed MB concentration was monitored by spectrophotometry. The desorption tests showed a remarkable elimination from the first 10 minutes. The desorption kinetics comprises two phases: a rapid kinetics between 0 and 30 minutes and a slow kinetics between 30 and 60 minutes. The desorption of the dye reaches a concentration aqual to 0.84 mg/l at pH = 4 at temperature = 80°C. For modeling, the coefficient of the Langmuir II model is greater than or equal to O.9893. The model of Langmuir III is less than or equal to 0.9373. The Freundlich model coefficient is 0.9842 or less. The desorption is thefore carried out on energy-homogeneous adsorption sites and without any interaction between the adsorbed cations of the dye. Experimental parameters such as pH, temperature and concentration of sodium chloride (NaCl) solution influence the desorption of MB. And the model of Langmuir II describes well the process of desorption of the MB.
文摘This research investigates the efficacy of activated Gmelina Wood Sawdust (GWS) as an adsorbent for the removal of methylene blue (MB) dye from aqueous solutions, in comparison with raw GWS. The study employs laboratory experiments to assess the percentage of dye removal across various temperature and pH conditions. The adsorption process is scrutinized under different parameters, encompassing contact time, initial dye concentration, adsorbent dosage, temperature, and pH. Results demonstrate that activated GWS surpasses its raw counterpart, showcasing superior MB dye removal percentages. Extended contact times increased initial dye concentrations, and higher adsorbent dosages contribute positively to removal efficiency, while temperature exhibits an inverse relationship with dye removal. Optimal adsorption occurs at a pH of 7.0, aligning with the adsorbent’s zero-point charge (pHzpc), underscoring the role of surface charge in the adsorption process. This study underscores the potential of activated GWS as an economical and promising adsorbent material for addressing pollutants. Furthermore, the utilization of activated carbon derived from abundant agricultural waste underscores an environmentally conscious approach to adsorption applications. The ability to tailor the size and properties of activated carbon particles opens avenues for optimizing adsorption capabilities, thereby presenting opportunities for enhanced water treatment solutions.
基金The study was supported by the Open Foundation of Key Laboratory of Carrying Capacity Assessment for Resource and Environment,Ministry of Natural Resources(Chinese Academy of Natural Resource Economics,China University of Geosciences Beijing,Institute of Geographical Sciences and Natural Resource Research,the Chinese Academy of Sciences)[CCA2019.08]Topics of Excellent Engineering in the Application of Social Sciences in Jiangsu Province,China[19SYC-105].
文摘Introduction:Large stocks of“blue carbon”exist in the ecosystems of coastal wetlands.This paper presents a case study of the Chinese city of Yancheng.First,through field surveys and laboratory analysis,changes in the organic carbon(OC)content in typical plant communities throughout the study area are described in detail.Second,an OC burial rate and economic value model is constructed to analyze the composition of the carbon sink values.Outcomes/other:The results are as follows:Of the typical plant communities,Spartina alterniflora has the highest OC content(5.80 g·kg-1),followed by Suaeda glauca(4.78 g·kg-1)and Phragmites australis(3.76 g·kg-1);the contemporary OC sedimentation rates are 2.01,1.48,and 1.22 cm·yr-1,respectively.Spartina alterniflora communities have the highest annual average carbon sink value($418.74/ha)in the study area,followed by Phragmites australis($176.29/ha)and Suaeda glauca($101.54/ha).Discussion:As a result of both the expansion of the Spartina alterniflora area and coastal erosion,the total OC value since 1987 has displayed two-stage characteristics:it first increased and then decreased.Conclusion:In recent years,the annual average decline in OC value has ranged from approximately$82,100 to$123,100(reference:the Sweden carbon tax provided by the World Bank,130$/ton)
基金supported by the National Natural Science Foundation of China Overseas and Hong Kong-Macao Scholars Collaborative Research Fund(Grant No.31728003)the Shanghai University Distinguished Professor(Oriental Scholars)Program(Grant No.JZ2016006)
文摘Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plants and microbes; and stored in nearshore sediments and soils; as well as the carbon transported from the coast to the ocean and ocean floor. The carbon sequestration capacity per unit area of coastal blue carbon is far greater than that of the terrestrial carbon pool. The mechanisms and controls of the carbon sink from salt marshes, mangroves, seagrasses, the aquaculture of shellfish and macroalgae, and the microbial carbon pump need to be further studied. The methods to quantify coastal blue carbon include carbon flux measurements, carbon pool measurements, manipulative experiments, and modeling. Restoring, conserving, and enhancing blue carbon will increase carbon sinks and produce carbon credits, which could be traded on the carbon market. The need to tackle climate change and implement China's commitment to cut carbon emissions requires us to improve studies on coastal blue carbon science and policy. The knowledge learned from coastal blue carbon improves the conservation and restoration of salt marshes,mangroves, and seagrasses; enhances the function of the microbial carbon pump; and promotes sustainable aquaculture, such as ocean ranching.
基金This work was supported by the National Natural Science Foundation of China[42076176]Natural Science Foundation of Fujian Province of China[2020J01048]+1 种基金the Fundamental Research Funds for the Central Universities of China[20720210075]the Scientific and Technological Research Project for Social Welfare of Zhongshan City of China[2019B2005].
文摘Sequestration of blue carbon(C)in mangrove plantations depends on site characteristics and plantation management.This study evaluated the effects of plantation management on C sequestration at a C-neutral site in Xiamen,China.A field study was conducted on 10-year-old Sonneratia apetala and Kandelia obovata plantations(mono-Sa,mono-Ko)and a 15-year-old mixed plantation-.We found that mono-Ko had a significantly higher ecosystem C sequestration rate(3.32±0.62 kg C m^(-2)yr^(-1))than others when planted in the indirect shade of pioneer species.As a non-native species,Sonneratia performed better(0.57±0.01 kg C m^(-2)yr^(-1))when planted with Kandelia than in monotypic plantations.The temporary and long-term certified emission reduction(tCER and lCER)of the 12.98 ha mono-Ko was 4103.89 and 3693.50 net CO_(2)-e within 10 years,respectively.A literature review was conducted to show the compatibility of this study with other natural and plantation sites of China and Bangladesh(the native habitat for Sonneratia).The C sequestration of Sonneratia plantation sites in China is comparable with those in Bangladesh.However,the soil C accumulation rate for a Sonneratia monotypic plantation in Bangladesh decreased with age,yet the same did not occur in the plantations of China.
文摘This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),where some pools as seagrasses,and salt marshes,are highly efficient at capturing and storing carbon dioxide(CO_(2))from the atmosphere.Halophyte salt marsh plants were found to have a%C on Dry Weight(D.W.)of 32.26±3.91(mean±standard deviation),macrophytes 33.65±7.99,seagrasses 29.23±2.23,tamarisk 48.42±2.80,while the first 5 centimetres of wetland mud,on average,had a%C of 8.56±0.94.Like the ISO(International Organization for Standardization)14064 guideline to quantify the GHG(Greenhouse Gas)emission,we have studied the different conversion factors to be used as a practical tool for measurement the CO_(2)sink activity.These factors are essential to calculate the overall carbon reduction in a project located in temperate wetland using a method as the ISO 14064.2,UNI-BNeutral,VCS VERRA or other that will come.
基金Funded by the Project of Scientific Research Staring Foundation of Huaqiao University(11BS214)the Cultivate Project of National Natural Science Foundation of Huaqiao University(JBZR1214)the Educational research project for Young and middle-aged Teachers of Fujian Province(JAT160031)
文摘Hierarchically interconnected porous activated carbon have high specific surface areas, large numbers of dye adsorption sites, and interconnected pores for dye molecule diffusion and transportation. We prepared hierarchically interconnected porous banana peel activated carbons(BPACs) via a green method involving hydrothermal pretreatment and KOH activation, and systematically tested its methylene blue(MB) adsorption capacity. SEM showed that the BPACs had an interconnected porous structure and high-porosity surface. The Brunauer-Emmett-Teller surface area was 601.21 m^2/g, the adsorption average pore diameter was 2.11 nm, and the total pore volume was 0.32 cm^3/g. The MB adsorption capacity increased with increasing temperature, initial MB concentration, and pH value; it decreased with increasing adsorbent dosage. The adsorption isotherms and kinetic results for MB adsorption on BPACs were best described by the Langmuir adsorption and pseudo-second-order kinetic models, respectively. BPACs have a well-developed hierarchically interconnected porous structure, which increase the MB adsorption capacity and removal efficiency. Systematic MB adsorption tests show that BPAC is a highly efficient and easily available adsorbent.
文摘An attempt was made to prepare carbon coated tourmaline by mixing tourmaline powders and polyvinyl alcohol (PVA), followed by heat treatment in argon atmosphere. All samples were characterized by powder X-ray diffraction, high-resolution transmission electron microscopy, UV diffuse reflectance spectroscopy. Results showed that the residual carbon content was influenced by heat treatment temperature and the amount of PVA. The degradation of methylene blue by Carbon-coated tourmaline was also studied. The experiments pointed out that the carbon coated effects are best when the heating temperature was 900℃ and the weight content of PVA was 70%. And the tourmaline prepared under 900℃ in the oxidation atmosphere has the best degrade efficiency. The results also proved that the infrared radiation of tourmaline is not effect in the degrade progress.
基金Beijing Excellent Talents Training Fund(No.20061D0502200299)
文摘A batch fixed bed photoreactor,using felt-form activated carbon fibers(ACF)supported TiO2 photocatalyst(TiO2/ACF),was developed to carry out photocatalytic degradation of methylene blue(MB)solution.The effects of TiO2 particle size,loaded TiO2 amount,initial MB concentration,airflow rate and successive run on the decomposition rate were investigated.The results showed that photodegradation process followed a pseudo-first-order reaction kinetic law.The apparent first-order reaction constant kapp was larger than 0.047 min- 1 with half reaction time t1/2 shorter than 15 min,which was comparable to reported data using suspended Degussa P-25 TiO2 particles.The high degradation rate was mainly attributed to adsorption of MB molecules onto the surface of TiO2/ACF.The photocatalytic efficiency still remained nearly 90%after 12 successive runs,showing that successive usage of the designed photoreactor was possible.The synergic enhancement effect in combination of adsorption with ACF and photodegradation with TiO2 was proved by comparing MB removal rates in the successive degradation and adsorption runs,respectively.
文摘The effects of O<sub>2</sub> plasma treatment on the adsorption capacity of activated carbon (AC) were investigated by varying the plasma treatment times. The surface properties of the AC were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Zeta potential. The carbon was then applied to remove methylene blue (MB). The adsorption kinetics and isotherm were also studied. Results showed that pseudo-second-order kinetics was the most suitable model for describing the adsorption of MB onto AC. Equilibrium data were well fitted to the Freundlich isotherm model. The highest adsorption capacity resulted from 4 minutes of O2 plasma treatment. The 4-minute plasma treated AC had the best adsorption capacity for MB at 0.467 mg/mg. This work shows that activation of AC by plasma can open the micropore and increase the effectiveness of chemical removal.
基金This research is supported by the National Natural Science Foundation of China （Nos. 30770549 and 60571042）；Scientific Research Starting Foundation of Wuhan University （No. 502-265145）.
文摘A novel electrochemical method for the determination of sulphide at a multi-walled carbon nanotube-dihexadecyl hydrogen phosphate composite film coated glassy carbon electrode （MWNTs-DHP/GCE） based on in situ synthesis of methylene blue （MB） was established. 2007 Sheng Shui Hu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘Photodegradation of methylene blue (MB) and phenol (Ph) on TiO2 in presence of H-type and L-type activated carbons (AC) was studied. Photodegradation of MB and Ph were studied under two different lamps and results were compared against those obtained on a commercial TiO2. Apparent first order rate constant for the degradation of MB was higher in presence of any AC in comparison of TiO2 alone while only in presence of ACco2-800phenol was photodegradated in shorter irradiation time than that required by TiO2. It can be concluded that TiO2 enhances its photoactivity by a factor up to 8.7 in the degradation of MB in presence of AC and this effect is associated to the specific surface properties of AC.
文摘The present study aims to develop effective adsorption and oxidation of synthetic dye in wastewater by using the newly synthesized iron-amended activated carbon. Recently synthetic dye-containing wastewater has gained more attention due to its mass discharge, high toxicity and low biodegradation. For enhancing adsorption of dye and oxidative regeneration of dye-exhausted activated carbon, the novel amendment of iron-deposited granular activated carbon (GAC) was developed. It was to amend ferrous ion onto the acid-pretreated GAC when pH of iron solution was higher than the pH at point of zero charge (pH, pzc) of the GAC. Methylene blue (MB) in water was adsorbed onto the acid-treated iron- amended GAC (Fe-GAC) followed by single or multiple applications of H2O2. Batch experiments were carried out to study the adsorption isotherm and kinetics indicating adsorption of MB onto the Fe-GAC followed Langmuir isotherm and the pseudo-second order kinetics. The Fe-GACshowed the maximum adsorption capacity (qm) of 238.1 ± 0.78 mg/g which was higher than the virgin GAC with qm of 175.4 ± 13.6 mg/g at 20?C, pH 6 and the initial concentration of 20 - 200 mg/L. The heterogeneous Fenton oxidation of MB in the Fe-GAC revealedthat increasing the H2O2 loading from 7 to 140 mmol H2O2/mmol MB led to enhancing the oxidation efficiency of MB in the GAC from 62.6% to 100% due to the increased generation of hydroxyl radicals. Further enhancement of oxidation of MB in the Fe-GAC was made by the multiple application of H2O2 while minimizing OH radical scavenging often occurring at high concentration of H2O2. Therefore, the acid-treated iron-amended GAC would provide excellent adsorption capacity for MB and high oxidation efficiency of MB in the GAC with multiple applications of H2O2 and optimum iron loading.
文摘Porous carbons are extensively applied in gas separation, water purification, catalytic reaction, and electrochemical processing, attributing to their high specific surface area, large pore volume, chemical inertness, and good mechanical and thermal stability. The templating method is widely used to synthesize porous carbons with the controlled pore structure. Among them, preparation of diatomite-templated carbons attracts increasing attention because the obtained carbon has unique developed macropores and exhibits the promising application in adsorption and support of large-sized molecules. Macroporous diatomite-templated carbons are prepared by using additive or inherent solid acid sites of diatomite as the catalyst. The obtained carbons showed tubular and pillared macroporous structures, and had a few mesopores and micropores. However, the carbons possessed the small specific surface area and micropore volume, and thus showed the low adsorption capacity of small-sized molecules, such as methylene blue (MB). In this case, enhancement of porosity, especially microporosity, is necessary.
文摘The adsorption capacity of steam activated carbon prepared from Delonix regia pods SADRC for adsorption of Aniline Blue (AB) from aqueous solution was investigated under various experimental conditions. Batch study was conducted to assess the potential of the activated carbon for the removal of Aniline Blue from aqueous solution. Activated carbon prepared from Delonix regia pods was characterized using Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FTIR) Spectrophotometry before and after adsorption. The FTIR, spectra of SADRC pod before and after Aniline Blue adsorption were compared to study the impact of the Aniline Blue on the activated carbon developed from the Delonix regia pod. The stretching vibration band at 2169.54 cm-1 may be due to strong CN, while the stretching vibration band at around 1580 - 1650 cm-1 may be due to C=C stretching vibration. The bands around 1350 and 426.49 cm-1 are due to C-N and –SO3H group, respectively;this further suggests that some functional groups may be present on the surface of the carbon due to the low temperature of carbonization (300°C) of the adsorbent. Equilibrium isotherm studies were carried out by varying the following four parameters: initial concentration of Aniline Blue dye solution, solution pH and adsorbent dose. The equilibrium data obtained were more fitted to Langmuir than Freundlich isotherm models. The correlation coefficient value (R2) of the pseudo first order kinetics ranged from 0.08 to 0.85 while the R2 of the pseudo second order kinetics ranged from 0.963 to 0.997 at all the temperatures and initial concentrations considered. This suggests that the adsorption kinetics of Aniline Blue onto SADRC can be represented with pseudo second order kinetic model. This study showed that Delonix regia pod could be effectively used as an adsorbent for the removal of Aniline Blue from aqueous solutions over a wide range of concentration and temperature.
