A novel adsorbent named magnetic humic acid/chitosan composite(M-HA/Cs) was synthesized by decorating humic acid/chitosan composites with Fe_3O_4 nanoparticles. The adsorption capacity of M-HA/Cs was 1.5 times that of...A novel adsorbent named magnetic humic acid/chitosan composite(M-HA/Cs) was synthesized by decorating humic acid/chitosan composites with Fe_3O_4 nanoparticles. The adsorption capacity of M-HA/Cs was 1.5 times that of MCs. The effects of solution p H, initial concentration of Pb(Ⅱ) ions and adsorption temperature on Pb(Ⅱ) removal were examined in a batch system and further optimized using Box-Behnken analysis. The recommended optimum conditions are initial Pb(Ⅱ) concentration of 139.90 mg/L, initial pH of 4.98, and temperature of 43.97 oC. The adsorption processes could be well described by pseudo-second-order and Elovich models. Isotherm studies reveal that the adsorption process follows Sips and Temkin models. The thermodynamic study indicats that the adsorption process is spontaneous and exothermic. The potential mechanism of Pb(Ⅱ) on M-HA/Cs at pH 5 may be surface electrostatic attraction, coordination and hydrogen bonding.展开更多
Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environ...Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environmentally sustainable manner. Uganda’s natural resources such as soils and water bodies are threatened by contamination due to rapid industrialization and rural-urban migration in established Industrial Business Parks and planned oil and gas production at Albertine Graben Region. The low level of compliance to industrial effluents discharge standards relevant to specific environmental receptors and activities within oil and gas sector development pose a big question of how to sustain the biodiversity and natural resource management. Experiences from elsewhere have shown bioremediation as a viable and proven option to provide potentially manageable solutions to resulting pollution as a substitute to modern well-known remediation methods, for it is relatively cheaper, more efficient and minimal toxic byproducts after treatment. The most used bioremediation agents in different studies reviewed are bacterial species especially Pseudomonas and Bacillus, followed by Aspergillus a fungi species, microalgae and aquatic plants such as duckweed, macrophytes and pteridophytes. Regardless of the waste produced in either oil and gas sector or industries, these agents have shown greater biodegradation rates. Pseudomonas sp. has a degradation efficiency of oil compounds ranging from 90% - 100%, and Aspergillus sp. 75% - 95%. Some aquatic plants can thrive in created wetlands with relatively still water such as Phragmites australis which can degrade hydrocarbons especially Aromatic compounds with benzene ring up to 95%. It can thrive in salty water with high pH range of 4.8 - 8.2. With industrial wastewater, algae is the most dominant with the degradation rates varying from 65% -100% and bacteria at 70% - 90%. Most of the reported results are in the developed country context. In developing countries, duckweed is re展开更多
The purpose of this study was to examine the effects of supply chain integration on environmental performance of food manufacturing companies in Jordan. Data for this study were collected from one hundred and nineteen...The purpose of this study was to examine the effects of supply chain integration on environmental performance of food manufacturing companies in Jordan. Data for this study were collected from one hundred and nineteen food companies. To answer the study questions, and to verify its hypotheses, descriptive statistical tools and linear regression tests were used. The study results indicated that supply chain integration positively affected environmental performance. Additionally, the results showed that supply chain integration positively affected environmental control and pollution management.展开更多
基金Projects(41271332,51478470)supported by the National Natural Science Foundation of China
文摘A novel adsorbent named magnetic humic acid/chitosan composite(M-HA/Cs) was synthesized by decorating humic acid/chitosan composites with Fe_3O_4 nanoparticles. The adsorption capacity of M-HA/Cs was 1.5 times that of MCs. The effects of solution p H, initial concentration of Pb(Ⅱ) ions and adsorption temperature on Pb(Ⅱ) removal were examined in a batch system and further optimized using Box-Behnken analysis. The recommended optimum conditions are initial Pb(Ⅱ) concentration of 139.90 mg/L, initial pH of 4.98, and temperature of 43.97 oC. The adsorption processes could be well described by pseudo-second-order and Elovich models. Isotherm studies reveal that the adsorption process follows Sips and Temkin models. The thermodynamic study indicats that the adsorption process is spontaneous and exothermic. The potential mechanism of Pb(Ⅱ) on M-HA/Cs at pH 5 may be surface electrostatic attraction, coordination and hydrogen bonding.
文摘Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environmentally sustainable manner. Uganda’s natural resources such as soils and water bodies are threatened by contamination due to rapid industrialization and rural-urban migration in established Industrial Business Parks and planned oil and gas production at Albertine Graben Region. The low level of compliance to industrial effluents discharge standards relevant to specific environmental receptors and activities within oil and gas sector development pose a big question of how to sustain the biodiversity and natural resource management. Experiences from elsewhere have shown bioremediation as a viable and proven option to provide potentially manageable solutions to resulting pollution as a substitute to modern well-known remediation methods, for it is relatively cheaper, more efficient and minimal toxic byproducts after treatment. The most used bioremediation agents in different studies reviewed are bacterial species especially Pseudomonas and Bacillus, followed by Aspergillus a fungi species, microalgae and aquatic plants such as duckweed, macrophytes and pteridophytes. Regardless of the waste produced in either oil and gas sector or industries, these agents have shown greater biodegradation rates. Pseudomonas sp. has a degradation efficiency of oil compounds ranging from 90% - 100%, and Aspergillus sp. 75% - 95%. Some aquatic plants can thrive in created wetlands with relatively still water such as Phragmites australis which can degrade hydrocarbons especially Aromatic compounds with benzene ring up to 95%. It can thrive in salty water with high pH range of 4.8 - 8.2. With industrial wastewater, algae is the most dominant with the degradation rates varying from 65% -100% and bacteria at 70% - 90%. Most of the reported results are in the developed country context. In developing countries, duckweed is re
文摘The purpose of this study was to examine the effects of supply chain integration on environmental performance of food manufacturing companies in Jordan. Data for this study were collected from one hundred and nineteen food companies. To answer the study questions, and to verify its hypotheses, descriptive statistical tools and linear regression tests were used. The study results indicated that supply chain integration positively affected environmental performance. Additionally, the results showed that supply chain integration positively affected environmental control and pollution management.
