Various applications of volume dielectric barrier discharges(DBDs)with airflows have attracted significant attention such as in the fields of plasma medicine,surface modification,ozone synthesis,etc.In this work,the n...Various applications of volume dielectric barrier discharges(DBDs)with airflows have attracted significant attention such as in the fields of plasma medicine,surface modification,ozone synthesis,etc.In this work,the nonlinearity characteristics of DBDs in initiating and extinguishing boundaries with airflows are experimentally investigated.It is found that the difference between initiating pulse repetition frequencies(PRFs)and extinguishing PRFs is affected by the addition of airflows.A hysteresis region is produced between these two PRFs.A topological rule of Thom's classification theorem is proposed to investigate the hysteresis phenomenon of discharges with airflows.It is concluded that the discharge state is dependent on the operation route.The discharge state would transit from initiating to extinguishing,or in the opposite direction,while passing along a specific operation route.Based on the topological method,two nonlinear laws of discharge structure transition under the typical operation routes are predicted and verified in the discharge experiments.展开更多
近年来,卡马西平因其高额的使用量,在自然水体中的检出率逐渐增加,寻找新的高效清洁的方法对其进行治理也成为了一项新的挑战。本研究采用同轴双介质阻挡放电反应器,以CO2和氩气为放电气体,对以水膜形式流过放电区域的卡马西平溶液进行...近年来,卡马西平因其高额的使用量,在自然水体中的检出率逐渐增加,寻找新的高效清洁的方法对其进行治理也成为了一项新的挑战。本研究采用同轴双介质阻挡放电反应器,以CO2和氩气为放电气体,对以水膜形式流过放电区域的卡马西平溶液进行有效降解。重点研究了不同比例CO2/Ar气氛等离子体放电对CO2转化率的影响、不同放电参数对卡马西平降解率的影响、活性物质的产生和卡马西平的降解机理。结果表明,当CO2/Ar = 1/9,总气体流量为300 mL/min时,CO2的转化率(16.84%)和卡马西平的降解率(87.58%)均达到了最高。同时随着气体中CO2/Ar比例的减小,·OH、O3和H2O2等活性物质的含量也有了一定程度的提高,这主要与放电过程中促进CO2的碰撞和解离,产生活性氧原子,并通过传质等在液相中发生一系列化学反应,形成液相活性物质相关。最后通过液相色谱–质谱联用仪对卡马西平的降解中间产物进行检测,从而分析出卡马西平可能的降解路径。本研究为等离子体降解水体中有机污染物、CO2的转化再利用提供了一种新的思路。In recent years, the detection rate of carbamazepine in natural water bodies has gradually increased due to its high usage, and it has become a new challenge to find a new efficient and clean method to treat carbamazepine. In this study, the carbamazepine solution flowing through the discharge area in the form of water film was effectively degraded by using CO2 and argon as discharge gases in a coaxial double-dielectric barrier discharge reactor. The effect of different ratio of CO2/Ar atmosphere plasma discharge on CO2 conversion, the effect of different discharge parameters on carbamazepine degradation rate, the production of active substances and the degradation mechanism of carbamazepine were studied. The results showed that when CO2/Ar = 1/9 and the total gas flow rate was 300 mL/min, the CO2 conversion rate (16.84%) and carbamazepine degradation rate (87.58%) reached the highest. At the same time, with the decrease of the CO2/Ar ratio in the gas, the content of active substances such as ·OH, O3 and H2O2 also increases to a certain extent, which is mainly related to the promotion of the collision and dissociation of CO2 during the discharge process, the generation of reactive oxygen atoms, and the formation of liquid phase active substances through a series of chemical reactions such as mass transfer. Finally, the degradation intermediates of carbamazepine were detected by liquid chromatography-mass spectrometry, and the possible degradation path of carbamazepine was analyzed. This study provides a new idea for the plasma degradation of organic pollutants in water and the conversion and reuse of CO2.展开更多
Single-base editors,including cytosine base editors(CBEs)and adenine base editors(ABEs),facilitate accurate C·G to T·A and A·T to G·C,respectively,holding promise for the precise modeling and treat...Single-base editors,including cytosine base editors(CBEs)and adenine base editors(ABEs),facilitate accurate C·G to T·A and A·T to G·C,respectively,holding promise for the precise modeling and treatment of human hereditary disorders.Efficient base editing and expanded base conversion range have been achieved in human cells through base editors fusing with Rad51 DNA binding domain(Rad51DBD),such as hyA3A-BE4max.Here,we show that hyA3A-BE4max catalyzes C-to-T substitution in the zebrafish genome and extends editing positions(C_(12)-C_(16))proximal to the protospacer adjacent motif.We develop a codon-optimized counterpart zhyA3A-CBE5,which exhibits substantially high C-to-T conversion with 1.59-to 3.50-fold improvement compared with the original hyA3A-BE4max.With these tools,disease-relevant hereditary mutations can be more efficaciously generated in zebrafish.We introduce human genetic mutation rpl11^(Q42*)and abcc6a^(R1463C) by zhyA3A-CBE5 in zebrafish,mirroring Diamond-Blackfan anemia and Pseudoxanthoma Elasticum,respectively.Our study expands the base editing platform targeting the zebrafish genomic landscape and the application of single-base editors for disease modeling and gene function study.展开更多
Surface modification of fabrics is an effective way to endow them with antifouling properties while still maintaining their key advantages such as comfort,softness and stretchability.Herein,an atmospheric pressure die...Surface modification of fabrics is an effective way to endow them with antifouling properties while still maintaining their key advantages such as comfort,softness and stretchability.Herein,an atmospheric pressure dielectric barrier discharge(DBD)plasma method is demonstrated for the processing of silk fabrics using 1H,1H,2H,2H-perfluorodecyltriethoxysilane(PFDS)as the precursor.The results showed the successful grafting of PFDS groups onto the surface of silk fabrics without causing damage.Meanwhile,the gas temperature is rather low during the whole processing procedure,suggesting the non-equilibrium characteristics of DBD plasma.The influence on fabrics of the processing parameters(PFDS concentration,plasma treatment time and plasma discharge power)was systematically investigated.An optimum processing condition was determined to be a PFDS concentration of 8wt%,a plasma processing time of 40 s and a plasma power of 11.87 W.However,with prolonged plasma processing time or enhanced plasma power,the plasma-grafted PFDS films could be degraded.Further study revealed that plasma processing of silk fabrics with PFDS would lead to a change in their chemical composition and surface roughness.As a result,the surface energy of the fabrics was reduced,accompanied by improved water and oil repellency as well as enhanced antifouling performance.Besides,the plasma-grafted PFDS films also had good durability and stability.By extending the method to polyester and wool against different oil-/water-based stains,the DBD plasma surface modification technique demonstrated good versatility in improving the antifouling properties of fabrics.This work provides guidance for the surface modification of fabrics using DBD plasma to confer them with desirable functionalities.展开更多
This study comprehensively investigates the degradation performance and mechanism of environmental persistent pollutants(EPs)by combining experimental and theoretical calculations with dielectric barrier discharge(DBD...This study comprehensively investigates the degradation performance and mechanism of environmental persistent pollutants(EPs)by combining experimental and theoretical calculations with dielectric barrier discharge(DBD)plasma synergized with persulfate.The findings demonstrated that DBD plasma could generate reactive radicals,including·OH,^(1)O_(2) and·O_(2)^(-),which primarily activate persulfate through OH and·O_(2)^(-)to produce the potent oxidizing radical SO_4^(-).This process facilitated enhanced degradation and mineralization of MeP wastewater.The performance of DBD/persulfute(PS)in degrading MeP was evaluated by kinetics,energy efficiency,and co-factor calculations,combined with degradation under different influencing factors.The actives in the system were analyzed by free radical scavenging assays and UV spectrophotometric testing to determine their effects.The findings indicated that persulfate was effectively activated by DBD plasma and that·O_(2)^(-)played a significant role.The presence of persulfate elevated the levels of H_(2)O_(2) and O_(3) in the solution.The intermediates formed during the degradation of MeP were detected using LC-MS and then analyzed alongside density-functional theory(DFT)chemical predictions to anticipate the reactive sites and deduce the potential degradation pathways of methylparaben(MeP).Toxicity evaluation software confirmed that the PS/DBD system reduces acute and developmental toxicity in the water column.The study showed that DBD plasma-activated persulfate was successful in addre ssing newly identified contaminants.展开更多
基金supported by National Natural Science Foundation of China(Nos.51676053 and 91741204)。
文摘Various applications of volume dielectric barrier discharges(DBDs)with airflows have attracted significant attention such as in the fields of plasma medicine,surface modification,ozone synthesis,etc.In this work,the nonlinearity characteristics of DBDs in initiating and extinguishing boundaries with airflows are experimentally investigated.It is found that the difference between initiating pulse repetition frequencies(PRFs)and extinguishing PRFs is affected by the addition of airflows.A hysteresis region is produced between these two PRFs.A topological rule of Thom's classification theorem is proposed to investigate the hysteresis phenomenon of discharges with airflows.It is concluded that the discharge state is dependent on the operation route.The discharge state would transit from initiating to extinguishing,or in the opposite direction,while passing along a specific operation route.Based on the topological method,two nonlinear laws of discharge structure transition under the typical operation routes are predicted and verified in the discharge experiments.
文摘近年来,卡马西平因其高额的使用量,在自然水体中的检出率逐渐增加,寻找新的高效清洁的方法对其进行治理也成为了一项新的挑战。本研究采用同轴双介质阻挡放电反应器,以CO2和氩气为放电气体,对以水膜形式流过放电区域的卡马西平溶液进行有效降解。重点研究了不同比例CO2/Ar气氛等离子体放电对CO2转化率的影响、不同放电参数对卡马西平降解率的影响、活性物质的产生和卡马西平的降解机理。结果表明,当CO2/Ar = 1/9,总气体流量为300 mL/min时,CO2的转化率(16.84%)和卡马西平的降解率(87.58%)均达到了最高。同时随着气体中CO2/Ar比例的减小,·OH、O3和H2O2等活性物质的含量也有了一定程度的提高,这主要与放电过程中促进CO2的碰撞和解离,产生活性氧原子,并通过传质等在液相中发生一系列化学反应,形成液相活性物质相关。最后通过液相色谱–质谱联用仪对卡马西平的降解中间产物进行检测,从而分析出卡马西平可能的降解路径。本研究为等离子体降解水体中有机污染物、CO2的转化再利用提供了一种新的思路。In recent years, the detection rate of carbamazepine in natural water bodies has gradually increased due to its high usage, and it has become a new challenge to find a new efficient and clean method to treat carbamazepine. In this study, the carbamazepine solution flowing through the discharge area in the form of water film was effectively degraded by using CO2 and argon as discharge gases in a coaxial double-dielectric barrier discharge reactor. The effect of different ratio of CO2/Ar atmosphere plasma discharge on CO2 conversion, the effect of different discharge parameters on carbamazepine degradation rate, the production of active substances and the degradation mechanism of carbamazepine were studied. The results showed that when CO2/Ar = 1/9 and the total gas flow rate was 300 mL/min, the CO2 conversion rate (16.84%) and carbamazepine degradation rate (87.58%) reached the highest. At the same time, with the decrease of the CO2/Ar ratio in the gas, the content of active substances such as ·OH, O3 and H2O2 also increases to a certain extent, which is mainly related to the promotion of the collision and dissociation of CO2 during the discharge process, the generation of reactive oxygen atoms, and the formation of liquid phase active substances through a series of chemical reactions such as mass transfer. Finally, the degradation intermediates of carbamazepine were detected by liquid chromatography-mass spectrometry, and the possible degradation path of carbamazepine was analyzed. This study provides a new idea for the plasma degradation of organic pollutants in water and the conversion and reuse of CO2.
基金supported by grants from Ministry of Science and Technology of the People's Republic of China(2018YFA0801004 and 2018YFA0800103)the National Natural Science Foundation of China(NSFC31530044,NSFC31970780,NSFC82202056).
文摘Single-base editors,including cytosine base editors(CBEs)and adenine base editors(ABEs),facilitate accurate C·G to T·A and A·T to G·C,respectively,holding promise for the precise modeling and treatment of human hereditary disorders.Efficient base editing and expanded base conversion range have been achieved in human cells through base editors fusing with Rad51 DNA binding domain(Rad51DBD),such as hyA3A-BE4max.Here,we show that hyA3A-BE4max catalyzes C-to-T substitution in the zebrafish genome and extends editing positions(C_(12)-C_(16))proximal to the protospacer adjacent motif.We develop a codon-optimized counterpart zhyA3A-CBE5,which exhibits substantially high C-to-T conversion with 1.59-to 3.50-fold improvement compared with the original hyA3A-BE4max.With these tools,disease-relevant hereditary mutations can be more efficaciously generated in zebrafish.We introduce human genetic mutation rpl11^(Q42*)and abcc6a^(R1463C) by zhyA3A-CBE5 in zebrafish,mirroring Diamond-Blackfan anemia and Pseudoxanthoma Elasticum,respectively.Our study expands the base editing platform targeting the zebrafish genomic landscape and the application of single-base editors for disease modeling and gene function study.
基金the financial support from National Natural Science Foundation of China(Nos.22078125 and 52004102)Postdoctoral Science Foundation of China(No.2023M741472)。
文摘Surface modification of fabrics is an effective way to endow them with antifouling properties while still maintaining their key advantages such as comfort,softness and stretchability.Herein,an atmospheric pressure dielectric barrier discharge(DBD)plasma method is demonstrated for the processing of silk fabrics using 1H,1H,2H,2H-perfluorodecyltriethoxysilane(PFDS)as the precursor.The results showed the successful grafting of PFDS groups onto the surface of silk fabrics without causing damage.Meanwhile,the gas temperature is rather low during the whole processing procedure,suggesting the non-equilibrium characteristics of DBD plasma.The influence on fabrics of the processing parameters(PFDS concentration,plasma treatment time and plasma discharge power)was systematically investigated.An optimum processing condition was determined to be a PFDS concentration of 8wt%,a plasma processing time of 40 s and a plasma power of 11.87 W.However,with prolonged plasma processing time or enhanced plasma power,the plasma-grafted PFDS films could be degraded.Further study revealed that plasma processing of silk fabrics with PFDS would lead to a change in their chemical composition and surface roughness.As a result,the surface energy of the fabrics was reduced,accompanied by improved water and oil repellency as well as enhanced antifouling performance.Besides,the plasma-grafted PFDS films also had good durability and stability.By extending the method to polyester and wool against different oil-/water-based stains,the DBD plasma surface modification technique demonstrated good versatility in improving the antifouling properties of fabrics.This work provides guidance for the surface modification of fabrics using DBD plasma to confer them with desirable functionalities.
基金supported by the National Natural Science Foundation of China(50867003)。
文摘This study comprehensively investigates the degradation performance and mechanism of environmental persistent pollutants(EPs)by combining experimental and theoretical calculations with dielectric barrier discharge(DBD)plasma synergized with persulfate.The findings demonstrated that DBD plasma could generate reactive radicals,including·OH,^(1)O_(2) and·O_(2)^(-),which primarily activate persulfate through OH and·O_(2)^(-)to produce the potent oxidizing radical SO_4^(-).This process facilitated enhanced degradation and mineralization of MeP wastewater.The performance of DBD/persulfute(PS)in degrading MeP was evaluated by kinetics,energy efficiency,and co-factor calculations,combined with degradation under different influencing factors.The actives in the system were analyzed by free radical scavenging assays and UV spectrophotometric testing to determine their effects.The findings indicated that persulfate was effectively activated by DBD plasma and that·O_(2)^(-)played a significant role.The presence of persulfate elevated the levels of H_(2)O_(2) and O_(3) in the solution.The intermediates formed during the degradation of MeP were detected using LC-MS and then analyzed alongside density-functional theory(DFT)chemical predictions to anticipate the reactive sites and deduce the potential degradation pathways of methylparaben(MeP).Toxicity evaluation software confirmed that the PS/DBD system reduces acute and developmental toxicity in the water column.The study showed that DBD plasma-activated persulfate was successful in addre ssing newly identified contaminants.
