The management of livestock waste is an effective way to achieve emission reduction and carbon fixation in agriculture and rural areas.At present,aerobic composting and anaerobic fermentation are widely used in livest...The management of livestock waste is an effective way to achieve emission reduction and carbon fixation in agriculture and rural areas.At present,aerobic composting and anaerobic fermentation are widely used in livestock waste treatment technology.In this study,pig manure management was taken as an example,a comprehensive environmental load index was constructed to quantitatively evaluate the environmental impacts of global warming,environmental acidification,eutrophication,and photochemical ozone synthesis during aerobic composting and anaerobic fermentation based on the life cycle assessment.The results showed that the potential values of aerobic composting and anaerobic fermentation were similar,and the order was global warming,environmental acidification,eutrophication,and photochemical ozone synthesis.Anaerobic fermentation contributed more to global warming,while aerobic composting contributed more to environmental acidification,eutrophication,and photochemical ozone synthesis.In addition,the environmental load index of aerobic composting was significantly higher than that of anaerobic fermentation.There were certainly regional differences in the environmental load index,and the environmental impact effect of anaerobic fermentation was low and more environmentally friendly.These findings provided a technical basis for livestock manure management in different regions of China,which was conducive to promoting animal husbandry emission reduction and carbon sequestration.展开更多
An unprecedented palladium-catalyzed asymmetric carbamoyl-carbonylation of tethered alkenes with CO and alcohols has been developed.This reaction provided an efficient route to access oxindoles andγ-lactams bearingβ...An unprecedented palladium-catalyzed asymmetric carbamoyl-carbonylation of tethered alkenes with CO and alcohols has been developed.This reaction provided an efficient route to access oxindoles andγ-lactams bearingβ-carbonyl substituted quaternary carbons in good yields with excellent chemo-,regio-and enantioselectivity.Gram-scale synthetic capability and facile transformations of the products to chiral spirooxindole and other functional molecules further illustrated the practicability of this reaction.展开更多
Many of the commonly used pharmaceuticals and biologically active natural products are nitrogencontaining compounds.Recently,the transitionmetal-catalyzed or the radical-mediated 1,2-carboamination of alkenes has been...Many of the commonly used pharmaceuticals and biologically active natural products are nitrogencontaining compounds.Recently,the transitionmetal-catalyzed or the radical-mediated 1,2-carboamination of alkenes has been well explored to access amine scaffolds.However,synthetic strategies toward the 1,1-carboamination of alkenes are severely limited.Herein,we describe a method to achieve the 1,1-arylamination using readily available building blocks enabled by palladium catalysis.This sequential three step-Heck arylation,metal migration,followed by aza-1,6-Micheal addition process exhibits excellent chemo-and regioselectivity.To showcase the potential as a method for diversity-oriented drug discovery,the modification of numerous structurally complex bioactive molecules was also successfully performed.展开更多
基金This work was financially supported by the Public Welfare Industry(Agriculture)Research Funding Project(Grant No.201303091).
文摘The management of livestock waste is an effective way to achieve emission reduction and carbon fixation in agriculture and rural areas.At present,aerobic composting and anaerobic fermentation are widely used in livestock waste treatment technology.In this study,pig manure management was taken as an example,a comprehensive environmental load index was constructed to quantitatively evaluate the environmental impacts of global warming,environmental acidification,eutrophication,and photochemical ozone synthesis during aerobic composting and anaerobic fermentation based on the life cycle assessment.The results showed that the potential values of aerobic composting and anaerobic fermentation were similar,and the order was global warming,environmental acidification,eutrophication,and photochemical ozone synthesis.Anaerobic fermentation contributed more to global warming,while aerobic composting contributed more to environmental acidification,eutrophication,and photochemical ozone synthesis.In addition,the environmental load index of aerobic composting was significantly higher than that of anaerobic fermentation.There were certainly regional differences in the environmental load index,and the environmental impact effect of anaerobic fermentation was low and more environmentally friendly.These findings provided a technical basis for livestock manure management in different regions of China,which was conducive to promoting animal husbandry emission reduction and carbon sequestration.
基金This work was supported by the National Natural Science Foundation of China(22071267)the Open Project of State Key Laboratory of Natural Medicines(SKLNMZZ202023)the Innovation Team of“the Double-First Class”Disciplines(CPU2018GY35).
文摘An unprecedented palladium-catalyzed asymmetric carbamoyl-carbonylation of tethered alkenes with CO and alcohols has been developed.This reaction provided an efficient route to access oxindoles andγ-lactams bearingβ-carbonyl substituted quaternary carbons in good yields with excellent chemo-,regio-and enantioselectivity.Gram-scale synthetic capability and facile transformations of the products to chiral spirooxindole and other functional molecules further illustrated the practicability of this reaction.
基金supported by the National Science Foundation of China(no.22071267)the National Science and Technology Major Project“Key New Drug Creation and Manufacturing Program,”China(no.2020ZX09201015)+1 种基金the Innovation Team of the“DoubleFirst Class Initiative”(nos.CPU2018GY04 and CPU2018GY35)the Foundation of the Open Project of State Key Laboratory of Natural Medicines(no.SKLNMZZ202023).
文摘Many of the commonly used pharmaceuticals and biologically active natural products are nitrogencontaining compounds.Recently,the transitionmetal-catalyzed or the radical-mediated 1,2-carboamination of alkenes has been well explored to access amine scaffolds.However,synthetic strategies toward the 1,1-carboamination of alkenes are severely limited.Herein,we describe a method to achieve the 1,1-arylamination using readily available building blocks enabled by palladium catalysis.This sequential three step-Heck arylation,metal migration,followed by aza-1,6-Micheal addition process exhibits excellent chemo-and regioselectivity.To showcase the potential as a method for diversity-oriented drug discovery,the modification of numerous structurally complex bioactive molecules was also successfully performed.