A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlo...A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlorohydrin. Then, hydrophilic amine groups were grafted to the modi?ed lignin structure through amination with ethylenediamine to obtain AEL. Subsequent acidi?cation of AEL led to the ionized aminated lignin (IAEL). The results of our analyses showed that the nitrogen content of AEL was 6.9%. Foaming and emulsifying experiments indicated that AEL had better foamability and emulsifying properties than IAEL. Surface tension tests showed that AEL and IAEL had similar critical micelle concentration (CMC). However, IAEL had lower surface tension (36.33 mN/m) than AEL (42.89 mN/m) at CMC. These results demonstrate the promising applicability of AEL as an emulsi?er and that of IAEL as feedstock in the production of detergent and dispersant.展开更多
The unique properties of carbon quantum dots (CQDs) make them promising materials in many ?elds. Herein, we present a facile method for the preparation of photo-luminescent CQDs using humins as the carbon precursor...The unique properties of carbon quantum dots (CQDs) make them promising materials in many ?elds. Herein, we present a facile method for the preparation of photo-luminescent CQDs using humins as the carbon precursor for the purpose of providing a high value-added solution for this “biomass conversion process waste”. The structure of the CQDs was analyzed, and the effects of reaction temperature and time on the CQDs’ ?uorescence were investigated. The results showed that humins were effectively carbonized during the reaction. The ?uorescence intensity of humin-based CQDs initially increased with reaction temperature and time, and subsequently decreased beyond 200℃ and 4 h. Polyaromatic structures and hydrophilic groups such as O-H, C-O, -COOH and C==O groups exist in the CQDs. The humin-based CQDs have the dimension of 3~7 nm with an average size of about 5.5 nm. The highest emission intensity of blue/cyan ?uorescence light at 440 nm is achieved on the excitation with UV light at the wavelength of 330 nm.展开更多
Mesophilic and thermophilic anaerobic fermentation performance of waste activated sludge(WAS)pretreated by enzymes catalysis associated with microbial community shifts were investigated.WAS disintegration was boosted ...Mesophilic and thermophilic anaerobic fermentation performance of waste activated sludge(WAS)pretreated by enzymes catalysis associated with microbial community shifts were investigated.WAS disintegration was boosted considerably by enzymolysis with 8750 mg/L of soluble COD release within 180 min.Mesophilic anaerobic fermentation(MAF)produced nearly equal VFA accumulation with over 3200 mg COD/L compared with that of thermophilic fermentation(TAF).Bacterial community consortia showed great shifting differences in dynamics of main T⁃RFs between MAF and TAF.Moreover,MAF was conducive to form intermediate bacterial community evenness compared to TAF,which preserved a robust function of VFA production.The enzymes catalysis prompted bio⁃energy(electricity)recovery potential of WAS organics via anaerobic fermentation(MAF/TAF)with evaluating electricity conversion efficiency of 0.75-0.82 kW·h/kg VSS(3.9 times higher than control test).Finally,this study proposed some novel thinking on future WAS treatment/management towards energy recovery coupled with energy⁃sufficient wastewater treatment by co⁃locating WAS anaerobic fermentation,MFC plant with wastewater treatment plant(s).展开更多
In this study,two-dimensional V2CTx MXene has been prepared by selectively etching Al layers from V2 AlC MAX phase by NaF+HCl etching at 90℃for 72 h and its performance as supercapacitor(SC)electrode were tested usin...In this study,two-dimensional V2CTx MXene has been prepared by selectively etching Al layers from V2 AlC MAX phase by NaF+HCl etching at 90℃for 72 h and its performance as supercapacitor(SC)electrode were tested using simulating seawater as electrolyte.V2CTx MXene-based electrodes shows a good capacitance of 181.1 F/g,which is in accordance with the volumetric specific capacitance of 317.8 F/cm^3,and with 89.1%capacitance retention even after 5000 cycle.Compared with other MXenes,V2CTx have better electrochemical performance as SC electrode.This work provides an innovative strategy to apply V2CTx MXene as SC electrode in safety and effective seawater electrolyte.展开更多
Two-dimensional carbide MXenes(Ti_3C_2T_x and V_2CT_x)were prepared by exfoliating MAX phases(Ti_3AlC_2 and V_2AlC)powders in the solution of sodium fluoride(NaF)and hydrochloric acid(HCl).The specific surface area(SS...Two-dimensional carbide MXenes(Ti_3C_2T_x and V_2CT_x)were prepared by exfoliating MAX phases(Ti_3AlC_2 and V_2AlC)powders in the solution of sodium fluoride(NaF)and hydrochloric acid(HCl).The specific surface area(SSA)of as-prepared Ti_3C_2T_x was 21 m^2/g,and that of V_2CT_x was 9 m^2/g.After intercalation with dimethylsulfoxide,the SSA of Ti_3C_2T_x was increased to 66 m^2/g;that of V_2CT_x was increased to 19 m^2/g.Their adsorption properties on carbon dioxide(CO_2)were investigated under 0–4 MPa at room temperature(298 K).Intercalated Ti_3C_2T_x had the adsorption capacity of 5.79 mmol/g,which is close to the capacity of many common sorbents.The theoretical capacity of Ti_3C_2T_x with the SSA of 496 m^2/g was up to 44.2 mmol/g.Additionally,due to high pack density,MXenes had very high volume-uptake capacity.The capacity of intercalated Ti_3C_2T_(x )measured in this paper was 502 V·v^(–1).This value is already higher than volume capacity of most known sorbents.These results suggest that MXenes have some advantage features to be researched as novel CO_2 capture materials.展开更多
Plant growth-promoting rhizobacteria(PGPR)contain various biocontrol bacteria with broad-spectrum antimicrobial activity,and their single species has been extensively applied to control crop diseases.The development o...Plant growth-promoting rhizobacteria(PGPR)contain various biocontrol bacteria with broad-spectrum antimicrobial activity,and their single species has been extensively applied to control crop diseases.The development of complex biocontrol community by mixing two or more PGPR members together is a promising strategy to enlarge the efficacy and scope of biocontrol.However,an effective method to assess the natural compatibility of PGPR members has not yet been established to date.Here,we developed such a tool by using the bacterial contactdependent antibacterial activity(CDAA)as a probe.We showed that the CDAA events are common in two-species interactions in the four selected representative PGPRs,represented by the incompatible interaction of Lysobacter enzymogenes strain OH11(OH11)and Lysobacter antibioticus strain OH13(OH13).We further showed that the CDAA between OH11 and OH13 is jointly controlled by a contact-dependent killing device,called the type IV secretion system(T4SS).By deleting the respective T4SS synthesis genes,the T4SS in both strains was co-inactivated and this step unlocked their natural CDAA,resulting in an engineered,compatible mutant alliance that co-displayed antibacterial and antifungal activity.Therefore,this study reveals that releasing bacterial CDAA is effective to rationally engineer the biocontrol community.展开更多
Objective:The objective was to explore the psychological experiences of laid-off workers in contemporary transitional China and to formulate a theoretical model of these.Methods:In-depth interviews of 26 laid-off work...Objective:The objective was to explore the psychological experiences of laid-off workers in contemporary transitional China and to formulate a theoretical model of these.Methods:In-depth interviews of 26 laid-off workers were conducted and analysed using grounded theory techniques.Results:Four themes underline the psychological processes of these laid-off workers-feeling of loss,feeling of physical pain,feeling of fatalism,and final acceptance.These are characterized by Chinese culture and its philosophy-feeling of loss is dominated by their loss of face(diu mi-anzi),physical pain is a somatization of their mental painfulness,their fatalism is traced back to the Chinese ancient theocratic concept of Tian Ming,and their acceptance of reality to their final making face(zheng mianzi)is sourced from both Confucianism and Daoism.Conclusion:The psychological experience of laid-off workers(or unemployed workers)is likely to have varied manifestations in different cultural contexts.The psychological processes of Chinese laid-off workers(or unemployed workers)might be different from those of laid-off workers in Western countries.A therapeutic intervention to cater for the needs of laid-off workers derived from the four themes might be effective.展开更多
基金supported by the Research Project for Hot Tracking Items of Beijing Forestry University(2017BLRD03)the National Natural Science Foundation of China(51603012)+1 种基金the Special Science and Technology Research Program of Beijing Forestry University(2016KJ02)the Fundamental Research Funds for the Central Universities(BLYJ2016-17,BLX2015-06)
文摘A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlorohydrin. Then, hydrophilic amine groups were grafted to the modi?ed lignin structure through amination with ethylenediamine to obtain AEL. Subsequent acidi?cation of AEL led to the ionized aminated lignin (IAEL). The results of our analyses showed that the nitrogen content of AEL was 6.9%. Foaming and emulsifying experiments indicated that AEL had better foamability and emulsifying properties than IAEL. Surface tension tests showed that AEL and IAEL had similar critical micelle concentration (CMC). However, IAEL had lower surface tension (36.33 mN/m) than AEL (42.89 mN/m) at CMC. These results demonstrate the promising applicability of AEL as an emulsi?er and that of IAEL as feedstock in the production of detergent and dispersant.
基金supported by the Research Project for Hot Tracking Items of Beijing Forestry University(2017BLRD03)the National Natural Science Foundation of China(51603012)Beijing Municipal Natural Science Foundation(6182031)
文摘The unique properties of carbon quantum dots (CQDs) make them promising materials in many ?elds. Herein, we present a facile method for the preparation of photo-luminescent CQDs using humins as the carbon precursor for the purpose of providing a high value-added solution for this “biomass conversion process waste”. The structure of the CQDs was analyzed, and the effects of reaction temperature and time on the CQDs’ ?uorescence were investigated. The results showed that humins were effectively carbonized during the reaction. The ?uorescence intensity of humin-based CQDs initially increased with reaction temperature and time, and subsequently decreased beyond 200℃ and 4 h. Polyaromatic structures and hydrophilic groups such as O-H, C-O, -COOH and C==O groups exist in the CQDs. The humin-based CQDs have the dimension of 3~7 nm with an average size of about 5.5 nm. The highest emission intensity of blue/cyan ?uorescence light at 440 nm is achieved on the excitation with UV light at the wavelength of 330 nm.
基金Sponsored by the Scientific Research Funds of Huaqiao University(Grant No.605-50Y18055).
文摘Mesophilic and thermophilic anaerobic fermentation performance of waste activated sludge(WAS)pretreated by enzymes catalysis associated with microbial community shifts were investigated.WAS disintegration was boosted considerably by enzymolysis with 8750 mg/L of soluble COD release within 180 min.Mesophilic anaerobic fermentation(MAF)produced nearly equal VFA accumulation with over 3200 mg COD/L compared with that of thermophilic fermentation(TAF).Bacterial community consortia showed great shifting differences in dynamics of main T⁃RFs between MAF and TAF.Moreover,MAF was conducive to form intermediate bacterial community evenness compared to TAF,which preserved a robust function of VFA production.The enzymes catalysis prompted bio⁃energy(electricity)recovery potential of WAS organics via anaerobic fermentation(MAF/TAF)with evaluating electricity conversion efficiency of 0.75-0.82 kW·h/kg VSS(3.9 times higher than control test).Finally,this study proposed some novel thinking on future WAS treatment/management towards energy recovery coupled with energy⁃sufficient wastewater treatment by co⁃locating WAS anaerobic fermentation,MFC plant with wastewater treatment plant(s).
基金supported by the National Natural Science Foundation of China(No.51772077)Program for Innovative Research Team(in Science and Technology)in the University of Henan Province(No.19IRTSTHN027)+2 种基金Natural Science Foundation of Henan Province(Nos.182300410228 and 182300410275)the China Postdoctoral Science Foundation(No.2019M652537)Henan Postdoctoral Foundation(No.19030065)。
文摘In this study,two-dimensional V2CTx MXene has been prepared by selectively etching Al layers from V2 AlC MAX phase by NaF+HCl etching at 90℃for 72 h and its performance as supercapacitor(SC)electrode were tested using simulating seawater as electrolyte.V2CTx MXene-based electrodes shows a good capacitance of 181.1 F/g,which is in accordance with the volumetric specific capacitance of 317.8 F/cm^3,and with 89.1%capacitance retention even after 5000 cycle.Compared with other MXenes,V2CTx have better electrochemical performance as SC electrode.This work provides an innovative strategy to apply V2CTx MXene as SC electrode in safety and effective seawater electrolyte.
基金supported by National Natural Science Foundation of China (Grant Nos. 51472075 and 51772077)Program for Innovative Research Team (in Science and Technology)in the University of Henan Province (Grant No. 19IRTSTHN027)Natural Science Foundation of Henan Province (Grant Nos. 182300410228 and 182300410275)
文摘Two-dimensional carbide MXenes(Ti_3C_2T_x and V_2CT_x)were prepared by exfoliating MAX phases(Ti_3AlC_2 and V_2AlC)powders in the solution of sodium fluoride(NaF)and hydrochloric acid(HCl).The specific surface area(SSA)of as-prepared Ti_3C_2T_x was 21 m^2/g,and that of V_2CT_x was 9 m^2/g.After intercalation with dimethylsulfoxide,the SSA of Ti_3C_2T_x was increased to 66 m^2/g;that of V_2CT_x was increased to 19 m^2/g.Their adsorption properties on carbon dioxide(CO_2)were investigated under 0–4 MPa at room temperature(298 K).Intercalated Ti_3C_2T_x had the adsorption capacity of 5.79 mmol/g,which is close to the capacity of many common sorbents.The theoretical capacity of Ti_3C_2T_x with the SSA of 496 m^2/g was up to 44.2 mmol/g.Additionally,due to high pack density,MXenes had very high volume-uptake capacity.The capacity of intercalated Ti_3C_2T_(x )measured in this paper was 502 V·v^(–1).This value is already higher than volume capacity of most known sorbents.These results suggest that MXenes have some advantage features to be researched as novel CO_2 capture materials.
文摘Plant growth-promoting rhizobacteria(PGPR)contain various biocontrol bacteria with broad-spectrum antimicrobial activity,and their single species has been extensively applied to control crop diseases.The development of complex biocontrol community by mixing two or more PGPR members together is a promising strategy to enlarge the efficacy and scope of biocontrol.However,an effective method to assess the natural compatibility of PGPR members has not yet been established to date.Here,we developed such a tool by using the bacterial contactdependent antibacterial activity(CDAA)as a probe.We showed that the CDAA events are common in two-species interactions in the four selected representative PGPRs,represented by the incompatible interaction of Lysobacter enzymogenes strain OH11(OH11)and Lysobacter antibioticus strain OH13(OH13).We further showed that the CDAA between OH11 and OH13 is jointly controlled by a contact-dependent killing device,called the type IV secretion system(T4SS).By deleting the respective T4SS synthesis genes,the T4SS in both strains was co-inactivated and this step unlocked their natural CDAA,resulting in an engineered,compatible mutant alliance that co-displayed antibacterial and antifungal activity.Therefore,this study reveals that releasing bacterial CDAA is effective to rationally engineer the biocontrol community.
文摘Objective:The objective was to explore the psychological experiences of laid-off workers in contemporary transitional China and to formulate a theoretical model of these.Methods:In-depth interviews of 26 laid-off workers were conducted and analysed using grounded theory techniques.Results:Four themes underline the psychological processes of these laid-off workers-feeling of loss,feeling of physical pain,feeling of fatalism,and final acceptance.These are characterized by Chinese culture and its philosophy-feeling of loss is dominated by their loss of face(diu mi-anzi),physical pain is a somatization of their mental painfulness,their fatalism is traced back to the Chinese ancient theocratic concept of Tian Ming,and their acceptance of reality to their final making face(zheng mianzi)is sourced from both Confucianism and Daoism.Conclusion:The psychological experience of laid-off workers(or unemployed workers)is likely to have varied manifestations in different cultural contexts.The psychological processes of Chinese laid-off workers(or unemployed workers)might be different from those of laid-off workers in Western countries.A therapeutic intervention to cater for the needs of laid-off workers derived from the four themes might be effective.