Rubber[Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.]plantations are the largest cultivated forest type in tropical China.Returning organic materials to the soil will help to maintain the quality and growth of ru...Rubber[Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.]plantations are the largest cultivated forest type in tropical China.Returning organic materials to the soil will help to maintain the quality and growth of rubber trees.Although many studies have demonstrated that organic waste materials can be used to improve soil fertility and structure to promote root growth,few studies have studied the eff ects of organic amendments on soil fertility and root growth in rubber tree plantations.Here,bagasse,coconut husk or biochar were applied with a chemical fertilizer to test their eff ects on soil properties after 6 months and compared with the eff ects of only the chemical fertilizer.Results showed that the soil organic matter content,total nitrogen,available phosphorus and available potassium after the chemical fertilizer(F)treatment were all signifi cantly lower than after the chemical fertilizer+bagasse(Fba),chemical fertilizer+coconut husk(Fco)or chemical fertilizer+biochar(Fbi)(p<0.05).Soil pH in all organic amendments was higher than in the F treatment,but was only signifi cantly higher in the Fbi treatment.In contrast,soil bulk density in the F treatment was signifi cantly higher than in treatments with the organic amendments(p<0.05).When compared with the F treatment,soil root dry mass increased signifi-cantly by 190%,176%and 33%in Fba,Fco and Fbi treatments,respectively(p<0.05).Similar results were found for root activity,number of root tips,root length,root surface area and root volume.Conclusively,the application of bagasse,coconut husk and biochar increased soil fertility and promoted root growth of rubber trees in the short term.However,bagasse and coconut husk were more eff ective than biochar in improving root growth of rubber trees.展开更多
Electro-upcycling of plastic waste into value-added chemicals/fuels is an attractive and sustainable way for plastic waste management.Recently,electrocatalytically converting polyethylene terephthalate(PET)into format...Electro-upcycling of plastic waste into value-added chemicals/fuels is an attractive and sustainable way for plastic waste management.Recently,electrocatalytically converting polyethylene terephthalate(PET)into formate and hydrogen has aroused great interest,while developing low-cost catalysts with high efficiency and selectivity for the central ethylene glycol(PET monomer)oxidation reaction(EGOR)remains a challenge.Herein,a high-performance nickel sulfide catalyst for plastic waste electro-upcycling is designed by a cobalt and chloride co-doping strategy.Benefiting from the interconnected ultrathin nanosheet architecture,dual dopants induced upshifting d band centre and facilitated in situ structural reconstruction,the Co and Cl co-doped Ni_(3)S_(2)(Co,Cl-NiS)outperforms the singledoped and undoped analogues for EGOR.The self-evolved sulfide@oxyhydroxide heterostructure catalyzes EG-to-formate conversion with high Faradic efficiency(>92%)and selectivity(>91%)at high current densities(>400 mA cm^(−2)).Besides producing formate,the bifunctional Co,Cl-NiS-assisted PET hydrolysate electrolyzer can achieve a high hydrogen production rate of 50.26 mmol h^(−1)in 2 M KOH,at 1.7 V.This study not only demonstrates a dual-doping strategy to engineer cost-effective bifunctional catalysts for electrochemical conversion processes,but also provides a green and sustainable way for plastic waste upcycling and simultaneous energy-saving hydrogen production.展开更多
The effects of additional oxidants,such as NaNO_(3),Na_(2)S_(2)O_(3),KClO_(4),and K_(2)Cr_(2)O_(7),on the supercritical water oxidation(SCWO)of tributyl phosphate(TBP)were studied.The coupling of an ionic oxidant with...The effects of additional oxidants,such as NaNO_(3),Na_(2)S_(2)O_(3),KClO_(4),and K_(2)Cr_(2)O_(7),on the supercritical water oxidation(SCWO)of tributyl phosphate(TBP)were studied.The coupling of an ionic oxidant with SCWO can effectively enhance the oxidative degradation ability of the system,thus increasing its organic-matter-removal efficiency at a reduced reaction temperature.Moreover,the addition of NaNO_(3),KClO_(4),or K_(2)Cr_(2)O_(7)could improve this efficiency at a reaction temperature of 500℃compared with that of the original system at 550℃.Additionally,based on the conditions adopted in this study,the addition of either of these oxidants could reduce the final total organic carbon(TOC)of the effluent from~500 to<100 ppm.Concurrently,the ionic oxidants could effectively improve the processing capacity of the SCWO system to reduce the scale of the equipment,as well as the amount of produced wastewater.Compared with KClO_(4)and Na_(2)S_(2)O_(3),the addition of 10 mmol/L NaNO_(3)and K_(2)Cr_(2)O_(7)to the organic feed could increase the processing capacity of the system from 4 to 10%while maintaining the TOC removal at>99%.The effects of the ionic oxidants on the gas products,including CO_(2),CO,H_(2),and CH_(4),as well as other organic gases,have also been studied.Among these gas products,CO_(2)accounted for the main gas product with a proportion of more than half.At<500℃,temperature significantly affected the as products(CO,H_(2),CH_(4),and other organic gases).However,the gas product was mainly CO_(2)when the temperature was increased to≥500℃.This study initially revealed the enhancement effect of ionic oxidants on SCWO,which still requires further research.展开更多
文摘Rubber[Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.]plantations are the largest cultivated forest type in tropical China.Returning organic materials to the soil will help to maintain the quality and growth of rubber trees.Although many studies have demonstrated that organic waste materials can be used to improve soil fertility and structure to promote root growth,few studies have studied the eff ects of organic amendments on soil fertility and root growth in rubber tree plantations.Here,bagasse,coconut husk or biochar were applied with a chemical fertilizer to test their eff ects on soil properties after 6 months and compared with the eff ects of only the chemical fertilizer.Results showed that the soil organic matter content,total nitrogen,available phosphorus and available potassium after the chemical fertilizer(F)treatment were all signifi cantly lower than after the chemical fertilizer+bagasse(Fba),chemical fertilizer+coconut husk(Fco)or chemical fertilizer+biochar(Fbi)(p<0.05).Soil pH in all organic amendments was higher than in the F treatment,but was only signifi cantly higher in the Fbi treatment.In contrast,soil bulk density in the F treatment was signifi cantly higher than in treatments with the organic amendments(p<0.05).When compared with the F treatment,soil root dry mass increased signifi-cantly by 190%,176%and 33%in Fba,Fco and Fbi treatments,respectively(p<0.05).Similar results were found for root activity,number of root tips,root length,root surface area and root volume.Conclusively,the application of bagasse,coconut husk and biochar increased soil fertility and promoted root growth of rubber trees in the short term.However,bagasse and coconut husk were more eff ective than biochar in improving root growth of rubber trees.
基金supported by the Australian Research Council(ARC)Discovery Project(DP220101139)Dr.Wei Wei acknowledges the support of the Australian Research Council(ARC)through Project DE220100530.
文摘Electro-upcycling of plastic waste into value-added chemicals/fuels is an attractive and sustainable way for plastic waste management.Recently,electrocatalytically converting polyethylene terephthalate(PET)into formate and hydrogen has aroused great interest,while developing low-cost catalysts with high efficiency and selectivity for the central ethylene glycol(PET monomer)oxidation reaction(EGOR)remains a challenge.Herein,a high-performance nickel sulfide catalyst for plastic waste electro-upcycling is designed by a cobalt and chloride co-doping strategy.Benefiting from the interconnected ultrathin nanosheet architecture,dual dopants induced upshifting d band centre and facilitated in situ structural reconstruction,the Co and Cl co-doped Ni_(3)S_(2)(Co,Cl-NiS)outperforms the singledoped and undoped analogues for EGOR.The self-evolved sulfide@oxyhydroxide heterostructure catalyzes EG-to-formate conversion with high Faradic efficiency(>92%)and selectivity(>91%)at high current densities(>400 mA cm^(−2)).Besides producing formate,the bifunctional Co,Cl-NiS-assisted PET hydrolysate electrolyzer can achieve a high hydrogen production rate of 50.26 mmol h^(−1)in 2 M KOH,at 1.7 V.This study not only demonstrates a dual-doping strategy to engineer cost-effective bifunctional catalysts for electrochemical conversion processes,but also provides a green and sustainable way for plastic waste upcycling and simultaneous energy-saving hydrogen production.
基金supported by the Shanghai Sail Program (No.19YF1458000)
文摘The effects of additional oxidants,such as NaNO_(3),Na_(2)S_(2)O_(3),KClO_(4),and K_(2)Cr_(2)O_(7),on the supercritical water oxidation(SCWO)of tributyl phosphate(TBP)were studied.The coupling of an ionic oxidant with SCWO can effectively enhance the oxidative degradation ability of the system,thus increasing its organic-matter-removal efficiency at a reduced reaction temperature.Moreover,the addition of NaNO_(3),KClO_(4),or K_(2)Cr_(2)O_(7)could improve this efficiency at a reaction temperature of 500℃compared with that of the original system at 550℃.Additionally,based on the conditions adopted in this study,the addition of either of these oxidants could reduce the final total organic carbon(TOC)of the effluent from~500 to<100 ppm.Concurrently,the ionic oxidants could effectively improve the processing capacity of the SCWO system to reduce the scale of the equipment,as well as the amount of produced wastewater.Compared with KClO_(4)and Na_(2)S_(2)O_(3),the addition of 10 mmol/L NaNO_(3)and K_(2)Cr_(2)O_(7)to the organic feed could increase the processing capacity of the system from 4 to 10%while maintaining the TOC removal at>99%.The effects of the ionic oxidants on the gas products,including CO_(2),CO,H_(2),and CH_(4),as well as other organic gases,have also been studied.Among these gas products,CO_(2)accounted for the main gas product with a proportion of more than half.At<500℃,temperature significantly affected the as products(CO,H_(2),CH_(4),and other organic gases).However,the gas product was mainly CO_(2)when the temperature was increased to≥500℃.This study initially revealed the enhancement effect of ionic oxidants on SCWO,which still requires further research.