Synthesis of spherical carbon beads with effective CO_2 capture capability is highly desirable for large scale application of CO2 sorption, but remains challenging. Herein, a facile and efficient strategy to prepare n...Synthesis of spherical carbon beads with effective CO_2 capture capability is highly desirable for large scale application of CO2 sorption, but remains challenging. Herein, a facile and efficient strategy to prepare nitrogen-doped hierarchically porous carbon spheres was developed via co-pyrolyzation of poly(vinylidene chloride) and melamine in alginate gel beads. In this approach, melamine not only serves as the nitrogen precursor, but also acts as a template for the macropores structures. The nitrogen contents in the hierarchically porous carbon spheres reach a high level, ranging from 11.8 wt% to 14.7 wt%, as the melamine amount increases. Owing to the enriched nitrogen functionalities and the special hierarchical porous structure, the carbon spheres exhibit an outstanding CO_2 capture performance, with the dynamic capacity of as much as about 7 wt% and a separation factor about 49 at 25 °C in a gas mixture of CO_2/N_2(0.5:99.5, v/v).展开更多
为探究基于专用短程通信(Dedicated Short Range Communication,DSRC)的港口运输车路协同的应用前景,对DSRC技术及其典型应用场景进行介绍,分析该技术的优缺点。阐述基于DSRC技术的港口车路协同的技术架构和应用场景,通过对比DSRC与蜂...为探究基于专用短程通信(Dedicated Short Range Communication,DSRC)的港口运输车路协同的应用前景,对DSRC技术及其典型应用场景进行介绍,分析该技术的优缺点。阐述基于DSRC技术的港口车路协同的技术架构和应用场景,通过对比DSRC与蜂窝车联网技术,指出DSRC面临的挑战并提出应对建议。分析认为目前基于被动式DSRC的车路协同技术在港口车辆身份认证方面具有一定的应用,但不能完全满足自动驾驶车辆与智能道路间实时信息交互的需求;我国已在DSRC标准层面针对自动驾驶需求明确实时信息交互方式,因此在DSRC技术层面还会不断演进,以满足更广泛的车路协同需求。展开更多
In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this ...In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this reaction.However,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to methanol.In the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction temperatures.The CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the activity.By finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption cycle.Higher performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.展开更多
Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and ecosystems.Adsorption and advanced oxidation methods have been exten-sively applied in SAs wastewater treatment.In this stu...Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and ecosystems.Adsorption and advanced oxidation methods have been exten-sively applied in SAs wastewater treatment.In this study,compared with Al^(3+)@BC500 and Fe^(3+)@BC500,La^(3+)@BC500 for activating persulfate(S2O82−)had the best effect removal per-formance of sulfadiazine(SDZ)and sulfamethoxazole(SMX).Morphology,acidity,oxygen-containing functional groups,and loading of La^(3+)@BC500 were analyzed by techniques,in-cluding EA,BET,XRD,XPS,FT-IR.XRD results show that with the increase of La^(3+)loading,the surface characteristics of biochar gradually changed from CaCO_(3)to LaCO_(3)OH.Through EPR technology,it is proved that LaCO_(3)OH on the surface of La^(3+)@BC500 can not only acti-vate S2O82−to generate SO_(4)^(−)•,but also to produce•OH.In the optimization experiment,the optimal dosage of La^(3+)is between 0.05 and 0.2(mol/L)/g.SDZ had a good removal effect at pH(5-9),but SMX had a good removal effect only at pH=3.Zeta potential also proves that the material is more stable under acidic conditions.The removal process of SDZ is more in accord with pseudo-first-order kinetics(R^(2)=0.9869),while SMX is more in line with pseudo-second order kinetics(R^(2)=0.9926).展开更多
基金supported by the National Key R&D Program of China (2016YFB0600902)the Dalian National Laboratory for Clean Energy (DNL180401)the National Natural Science Foundation of China (21925803)。
文摘Synthesis of spherical carbon beads with effective CO_2 capture capability is highly desirable for large scale application of CO2 sorption, but remains challenging. Herein, a facile and efficient strategy to prepare nitrogen-doped hierarchically porous carbon spheres was developed via co-pyrolyzation of poly(vinylidene chloride) and melamine in alginate gel beads. In this approach, melamine not only serves as the nitrogen precursor, but also acts as a template for the macropores structures. The nitrogen contents in the hierarchically porous carbon spheres reach a high level, ranging from 11.8 wt% to 14.7 wt%, as the melamine amount increases. Owing to the enriched nitrogen functionalities and the special hierarchical porous structure, the carbon spheres exhibit an outstanding CO_2 capture performance, with the dynamic capacity of as much as about 7 wt% and a separation factor about 49 at 25 °C in a gas mixture of CO_2/N_2(0.5:99.5, v/v).
文摘为探究基于专用短程通信(Dedicated Short Range Communication,DSRC)的港口运输车路协同的应用前景,对DSRC技术及其典型应用场景进行介绍,分析该技术的优缺点。阐述基于DSRC技术的港口车路协同的技术架构和应用场景,通过对比DSRC与蜂窝车联网技术,指出DSRC面临的挑战并提出应对建议。分析认为目前基于被动式DSRC的车路协同技术在港口车辆身份认证方面具有一定的应用,但不能完全满足自动驾驶车辆与智能道路间实时信息交互的需求;我国已在DSRC标准层面针对自动驾驶需求明确实时信息交互方式,因此在DSRC技术层面还会不断演进,以满足更广泛的车路协同需求。
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB36030200)the National Natural Science Foundation of China(Nos.21978286,21925803,and U19A2015)the Youth Innovation Promotion Association CAS,and the Young Topnotch Talents of Liaoning Province(Nos.XLYC2007082 and 1907170)。
文摘In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this reaction.However,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to methanol.In the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction temperatures.The CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the activity.By finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption cycle.Higher performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.
基金supported by the Key Projects of Intergovern-mental International Scientific and Technological Innovation Cooperation(No.2022YFE0120600)the National Natural Sci-ence Foundation of China(Nos.21978224 and U21A20322)the Science and Technology Commission of Shanghai Munic-ipality(Nos.21dz1202400,22dz1208300,and 22dz1209300).
文摘Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and ecosystems.Adsorption and advanced oxidation methods have been exten-sively applied in SAs wastewater treatment.In this study,compared with Al^(3+)@BC500 and Fe^(3+)@BC500,La^(3+)@BC500 for activating persulfate(S2O82−)had the best effect removal per-formance of sulfadiazine(SDZ)and sulfamethoxazole(SMX).Morphology,acidity,oxygen-containing functional groups,and loading of La^(3+)@BC500 were analyzed by techniques,in-cluding EA,BET,XRD,XPS,FT-IR.XRD results show that with the increase of La^(3+)loading,the surface characteristics of biochar gradually changed from CaCO_(3)to LaCO_(3)OH.Through EPR technology,it is proved that LaCO_(3)OH on the surface of La^(3+)@BC500 can not only acti-vate S2O82−to generate SO_(4)^(−)•,but also to produce•OH.In the optimization experiment,the optimal dosage of La^(3+)is between 0.05 and 0.2(mol/L)/g.SDZ had a good removal effect at pH(5-9),but SMX had a good removal effect only at pH=3.Zeta potential also proves that the material is more stable under acidic conditions.The removal process of SDZ is more in accord with pseudo-first-order kinetics(R^(2)=0.9869),while SMX is more in line with pseudo-second order kinetics(R^(2)=0.9926).
