Non-thermal plasma(NTP)is considered to be a promising technology for the removal of volatile organic compounds;however,its application is limited by low CO_(2) selectivity and undesirable by-products.To overcome thes...Non-thermal plasma(NTP)is considered to be a promising technology for the removal of volatile organic compounds;however,its application is limited by low CO_(2) selectivity and undesirable by-products.To overcome these issues,this paper discusses the degradation of chlorobenzene(CB)in systems of NTP coupled with catalysts,and the influence of catalyst locations in the NTP was investigated.In addition,the interaction between plasma and catalyst was also explored.The results indicated that the degradability of CB was remarkably improved through the combination of NTP with catalysts,and the formation of ozone was effectively inhibited.The degradation efficiency increased from 33.9%to 79.6%at 14 kV in the NTPcatalytic system,while the ozone concentration decreased from 437 to 237 mg m^(-3),and the degradation efficiency of in plasma catalysis(IPC)systems was superior to that of the post plasma catalysis system,while the inhibition ability of ozone exhibited an opposing trend.In the IPC system,the degradation efficiency was 87.7%at 14 k V,while the ozone concentration was151 mg m^(-3).Besides,the plasma did not destroy the pore structure and crystal structure of the catalyst,but affected the surface morphology and redox performance of the catalyst.Thus,NTP coupled catalytic system could improve the degradation performance of CB.Furthermore,the plasma discharge characteristics played a major role in the NTP synergistic catalytic degradation of CB.Finally,based on the experiment analysis results,the general reaction mechanism of CB degradation in an IPC reaction system was proposed.展开更多
C1 chemistrymainly involves the catalytic transformation of C1molecules(i.e.,CO,CO2,CH4 and CH3OH),which usually encounters thermodynamic and/or kinetic limitations.To address these limitations,non-thermal plasma(NTP)...C1 chemistrymainly involves the catalytic transformation of C1molecules(i.e.,CO,CO2,CH4 and CH3OH),which usually encounters thermodynamic and/or kinetic limitations.To address these limitations,non-thermal plasma(NTP)activated heterogeneous catalysis offers a number of advantages,such as relatively mild reaction conditions and energy efficiency,in comparison to the conventional thermal catalysis.This review presents the state-of-the-art for the application of NTP-catalysis towards C1 chemistry,including the CO2 hydrogenation,reforming of CH4 and CH3OH,and water-gas shift(WGS)reaction.In the hybrid NTP-catalyst system,the plasma-catalyst interactions aremultifaceted.Accordingly,this reviewalso includes a brief discussion on the fundamental research into themechanisms of NTP activated catalytic C1 chemistry,such as the advanced characterisation methods(e.g.,in situ diffuse reflectance infrared Fourier transform spectroscopy,DRIFTS),temperatureprogrammed plasma surface reaction(TPPSR),kinetic studies.Finally,prospects for the future research on the development of tailor-made catalysts for NTP-catalysis systems(which will enable the further understanding of its mechanism)and the translation of the hybrid technique to practical applications of catalytic C1 chemistry are discussed.展开更多
Particulate matter(PM)capture tests were carried out on clean diesel particulate filters(DPFs)under different loads(25%,50%,75%and 100%).DPFs were regenerated by a non-thermal plasma(NTP)injection device.Raman spectro...Particulate matter(PM)capture tests were carried out on clean diesel particulate filters(DPFs)under different loads(25%,50%,75%and 100%).DPFs were regenerated by a non-thermal plasma(NTP)injection device.Raman spectroscopy and x-ray photoelectron spectroscopy were used to investigate changes in the microstructure and element occurrence state of the sediment in DPF channel before and after regeneration.The order of the PM samples decreased before NTP treatment as the load increased;the amorphous carbon content was high,and the oxidationactivity was higher.After NTP treatment,the carbon atoms at the edge of the microcrystalline structure in the ash-PM samples were oxidized,and the structure was reorganized;in addition,the amorphous carbon content decreased,and the structure was more diversified.Before NTP,the C element of PM samples was the main component,and the content of the O element was relatively low.The C element occurred in the form of C–C,C–OH,and O–C=O functional groups,and O atoms were mainly combined with C–O.After NTP,the content of Na,P,S,Ca,and other inorganic elements in ash-PM samples was prominent because C atoms were removed by NTP active substances.There were two forms of S element occurrence(SO42-and SO32-);the proportion of SO42-was approximately 40%,and the proportion of SO32-was approximately60%.Study of the microstructure and element occurrence of the residues in the DPF channels improved our understanding of the mechanism of the low-temperature regeneration of DPFfrom NTP.展开更多
Non-thermal plasma has emerged as an effective treatment system against the latest class of highly recalcitrant and toxic environmental pollutants termed emerging contaminants(ECs).In the present work,a detailed exper...Non-thermal plasma has emerged as an effective treatment system against the latest class of highly recalcitrant and toxic environmental pollutants termed emerging contaminants(ECs).In the present work,a detailed experimental study is carried out to evaluate the efficacy of a non-thermal plasma jet with two dyes,Rd.B and Met.Blue,as model contaminants.The plasma jet provided a complete dye decoloration in 30 min with an applied voltage of 6.5 kV_(p-p).·OH,having the highest oxidation potential,acts as the main reactive species,which with direct action on contaminants also acts indirectly by getting converted into H_(2)O_(2)and O_(3).Further,the effect of critical operational parameters viz,sample pH,applied voltage(4.5–6.5 kV_(p-p)),conductivity(5–20 mS cm^(-1)),and sample distance on plasma treatment efficacy was also examined.Out of all the assessed parameters,the applied voltage and sample conductivity was found to be the most significant operating parameters.A high voltage and low conductivity favored the dye decoloration,while the pH effect was not that significant.To understand the influence of plasma discharge gas on treatment efficacy,all the experiments are conducted with argon and helium gases under the fixed geometrical configuration.Both the gases provided a similar dye decoloration efficiency.The DBD plasma system with complete dye removal also rendered maximum mineralization of 73%for Rd.B,and 60%for Met.Blue.Finally,the system's efficiency against the actual ECs(four pharmaceutical compounds,viz,metformin,atenolol,acetaminophen,and ranitidine)and microbial contaminant(E.coli)was also tested.The system showed effectivity in the complete removal of targeted pharmaceuticals and a log2.5 E.coli reduction.The present systematic characterization of dye degradation could be of interest to large communities working towards commercializing plasma treatment systems.展开更多
Mung bean(Vigna radiata)sprouts are widely consumed worldwide due to their high nutritional value.However,the low yield and microbial contamination of mung bean sprouts seriously reduces their economic value.This stud...Mung bean(Vigna radiata)sprouts are widely consumed worldwide due to their high nutritional value.However,the low yield and microbial contamination of mung bean sprouts seriously reduces their economic value.This study investigates the effects of non-thermal plasma on the quality and microbial reduction of mung bean sprouts by pretreatment of seeds in water for different times(0,1,3 and 6 min).The quality results showed that short-time plasma treatment(1 and 3 min)promoted seed germination and seedling growth,whereas long-time plasma treatment(6 min)had inhibitory effects.Plasma also had a similar dose effects on the total flavonoid and phenolic contents of mung bean sprouts.The microbiological results showed that plasma treatment achieved a reduction of native microorganisms ranging from 0.54 to 7.09 log for fungi and 0.29 to 6.80 log for bacteria at 96 h incubation.Meanwhile,plasma treatment could also efficiently inactivate artificially inoculated Salmonella typhimurium(1.83–6.22 log)and yeast(0.53–3.19 log)on mung bean seeds.The results of seed coat permeability tests and scanning electron microscopy showed that plasma could damage the seed coat structure,consequently increasing the electrical conductivity of mung bean seeds.The physicochemical analysis of plasma-treated water showed that plasma generated various long-and short-lived active species[nitric oxide radicals(NO·),hydroxyl radicals(·OH),singlet oxygen(1O2),hydrogen peroxide(H_(2)O_(2)),nitrate(NO_(3)^(-)),and nitrite(NO_(2)^(-))]in water,thus the oxidizability,acidity and conductivity of plasma-treated water were all increased in a treatment timedependent manner.The result for mimicked chemical mixtures confirmed the synergistic effect of activity of H_(2)O_(2),NO_(3)^(-)and NO_(2)^(-)on bacterial inactivation and plant growth promotion.Taken together,these results imply that plasma pretreatment of mung bean seeds in water with moderate oxidizability and acidity is an effective method to improve the yield of mung bean sprouts and reduce microbial contamination.展开更多
The presented work reports the selective catalytic reduction(SCR)of NO_(x) assisted by dielectric barrier discharge plasma via simulating marine diesel engine exhaust,and the experimental results demonstrate that the ...The presented work reports the selective catalytic reduction(SCR)of NO_(x) assisted by dielectric barrier discharge plasma via simulating marine diesel engine exhaust,and the experimental results demonstrate that the low-temperature activity of NH_(3)-SCR assisted by non-thermal plasma is enhanced significantly,particularly in the presence of a C_(3)H_(6) additive.Simultaneously,CeMnZrO_(x)@TiO_(2) exhibits strong tolerance to SO_(2) poisoning and superior catalytic stability.It is worthwhile to explore a new approach to remove NO_(x) from marine diesel engine exhaust,which is of vital significance for both academic research and practical applications.展开更多
NOx storage and reduction(NSR)technology has been regarded as one of the most promising strategies for the removal of nitric oxides(NOx)from lean-burn engines,and the potential of the plasma catalysis method for NOx r...NOx storage and reduction(NSR)technology has been regarded as one of the most promising strategies for the removal of nitric oxides(NOx)from lean-burn engines,and the potential of the plasma catalysis method for NOx reduction has been confirmed in the past few decades.This work reports the NSR of nitric oxide(NO)by combining non-thermal plasma(NTP)and Co/Pt/Ba/γ-Al2O3(Co/PBA)catalyst using methane as a reductant.The experimental results reveal that the NOx conversion of NSR assisted by NTP is notably enhanced compared to the catalytic efficiency obtained from NSR in the range of 150°C–350°C,and NOx conversion of the 8%Co/PBA catalyst reaches 96.8%at 350°C.Oxygen(O_(2))has a significant effect on the removal of NOx,and the NOx conversion increases firstly and then decreases when the O_(2)concentration ranges from 2%to 10%.Water vapor reduces the NOx storage capacity of Co/PBA catalysts on account of the competition for adsorption sites on the surface of Co/PBA catalysts.There is a negative correlation between sulfur dioxide(SO_(2))and NOx conversion in the NTP system,and the 8%Co/PBA catalyst exhibits higher NOx conversion compared to other catalysts,which shows that Co has a certain SO_(2)resistance.展开更多
An experimental system of De-NO with plasma-catalyst（Cu zeolite） was established to investigate the differences between De-NO with plasma-catalyst and De-NO only with plasma, to provide the instruction for selecting...An experimental system of De-NO with plasma-catalyst（Cu zeolite） was established to investigate the differences between De-NO with plasma-catalyst and De-NO only with plasma, to provide the instruction for selecting appropriate catalyst and operating condition. The characteristics of De-NO with plasma and De-NO with plasma-catalyst were investigated comparatively by experiments. The experimental results show that De-NO with plasma-catalyst has high NO removal rate; Cu zeolite is an effective catalyst which can promote NO removal rate in plasma remarkably; De-NO with plasma-catalyst should be operated at low temperature and the temperature has opposite effects on the function of catalyst and plasma; water vapor and O2 can increase the NO removal rate.展开更多
In this work,non-thermal plasma has been applied to treat polyacrylamide(PAM)wastewater.We have investigated the in fluence of the rule of PAM wastewater initial pH,solution concentration and discharge time,discharge ...In this work,non-thermal plasma has been applied to treat polyacrylamide(PAM)wastewater.We have investigated the in fluence of the rule of PAM wastewater initial pH,solution concentration and discharge time,discharge voltage on chemical oxygen demand(COD)degradation rate.At the same time,the effect of pH and discharge time on the viscosity removal rate of PAM solution was also studied.Then,the effect of pH on the viscosity removal rate of 1.0g 1^-1 PAM solution was studied separately.Through orthogonal test,the factors affecting the COD degradation rate of PAM wastewater were determined as follows:discharge time>discharge voltage>solution concentration>wastewater initial pH.1'he COD highest removal rate of PAM wastewater reached 85.74%,when the optimal conditions are as follows:discharge voltage 40 kV,discharge time 5 h,solution concentration 1.0 g 1^-1,pH 1.5.This research provides some basic data and new theoretical basis for PAM wastewater purification.展开更多
The present study evaluated the effect of non-thermal plasma on skin wound healing in BalB/c mice.Two 6-mm wounds along the both sides of the spine were created on the back of each mouse(n=80) by using a punch biopsy....The present study evaluated the effect of non-thermal plasma on skin wound healing in BalB/c mice.Two 6-mm wounds along the both sides of the spine were created on the back of each mouse(n=80) by using a punch biopsy.The mice were assigned randomly into two groups,with 40 animals in each group:a non-thermal plasma group in which the mice were treated with the non-thermal plasma;a control group in which the mice were left to heal naturally.Wound healing was evaluated on postoperative days(POD) 4,7,10 and 14(n=5 per group in each POD) by percentage of wound closure.The mice was euthanized on POD 1,4,7,10,14,21,28 and 35(n=1 in each POD).The wounds were removed,routinely fixed,paraffin-embedded,sectioned and HE-stained.A modified scoring system was used to evaluate the wounds.The results showed that acute inflammation peaked on POD 4 in non-thermal plasma group,earlier than in control group in which acute inflammation reached a peak on POD 7,and the acute inflammation scores were much lower in non-thermal group than in control group on POD 7(P<0.05).The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group(P<0.05).The re-epithelialization score and the neovasularization score were increased significantly in non-thermal group when compared with control group on POD 7 and 10(P<0.05 for all).The count of bacterial colonies was 103 CFU/mL on POD 4 and <20 CFU/mL on POD 7,significantly lower than that in control group(109 CFU/mL on POD 4 and >1012 CFU/mL on the POD 7)(P<0.05).It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colonization.展开更多
This review describes the application of non-thermal plasma(NTP) technology for high barrier layer fabrication in packaging area.NTP technology is considered to be the most prospective approaches for the barrier layer...This review describes the application of non-thermal plasma(NTP) technology for high barrier layer fabrication in packaging area.NTP technology is considered to be the most prospective approaches for the barrier layer fabrication over the past decades due to unpollution,high speed,low-costing.The applications of NTP technology have achieved numerous exciting results in high barrier packaging area.Now it seemly demands a detailed review to summarize the past works and direct the future developments.This review focuses on the different NTP resources applied in the high barrier area,the role of plasma surface modification on packaging film surface properties,and the deposition of different barrier coatings based on NTP technology.In particular,this review emphasizes the cutting-edge technologies of NTP on interlayer deposition with organic,inorganic for multilayer barriers fabrication.The future prospects of NTP technology in high barrier film areas are also described.展开更多
An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus (S. aureus). The plasma jet was generated by dielectric barrier discharge (DBD), which was characterized by electrical and ...An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus (S. aureus). The plasma jet was generated by dielectric barrier discharge (DBD), which was characterized by electrical and optical diagnostics. The survival curves of the bacteria showed that the plasma jet could effectively inactivate 10 6 cells of S. aureus within 120 seconds and the sterilizing efficiency depended critically on the discharge parameter of the applied voltage. It was further confirmed by scanning electron microscopy (SEM) that the cell morphology was seriously damaged by the plasma treatment. The plasma sterilization mechanism of S. aureus was attributed to the active species of OH, N 2 + and O, which were generated abundantly in the plasma jet and characterized by OES. Our findings suggest a convenient and low-cost way for sterilization and inactivation of bacteria.展开更多
In this paper,the characteristics of detonation combustion ignited by AC-driven non-thermal plasma and spark plug in air/acetylene mixture have been compared in a doubletube experiment system.The two tubes had the sam...In this paper,the characteristics of detonation combustion ignited by AC-driven non-thermal plasma and spark plug in air/acetylene mixture have been compared in a doubletube experiment system.The two tubes had the same structure,and their closed ends were installed with a plasma generator and a spark plug,respectively.The propagation characteristics of the flame were measured by pressure sensors and ion probes.The experiment results show that,compared with a spark plug,the non-thermal plasma obviously broadened the range of equivalence ratio when the detonation wave could develop successfully,it also heightened the pressure value of detonation wave.Meanwhile,the detonation wave development time and the entire flame propagation time were reduced by half.All of these advantages benefited from the larger ignition volume when a non-thermal plasma was applied.展开更多
Improvement of polytetrafluoroethylene surface energy by non-thermal plasma treatmentis presented,using a nanosecond-positive-edge repetitive pulsed dielectric barrier dischargegenerator in atmospheric air.The electri...Improvement of polytetrafluoroethylene surface energy by non-thermal plasma treatmentis presented,using a nanosecond-positive-edge repetitive pulsed dielectric barrier dischargegenerator in atmospheric air.The electrical parameters including discharging power,peak anddensity of micro-discharge current were calculated,and the electron energy was estimated.Surfacetreatment experiments of polytetrafluoroethylene films were conducted for both differentapplied voltages and different treating durations.Results show that the surface energy of polytetrafluoroethylenefilm could be improved to 40 mJ/m^2 or more by plasma treatment.Surfaceroughness measurement and surface X-ray photoelectron spectroscopy analysis indicate that thereare chemical etching and implantation of polar oxygen groups in the sample surface treating process,resulting in the improvement of the sample surface energy.Compared with an AC sourceof 50 Hz,the dielectric barrier discharges generated by a repetitive pulsed source could providehigher peak power,lower mean power,larger micro-discharge current density and higher electronenergy.Therefore,with the same applied peak voltage and treating duration,the improvementof polytetrafluoroethylene surface energy using repetitive pulsed plasma is more effective,and theplasma treatment process based on repetitive pulsed dielectric barrier discharges in air is thusfeasible and applicable.展开更多
The non-thermal plasma created by high voltage pulsed power supply can be usedto remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It isnovel to apply the magnetic field in re...The non-thermal plasma created by high voltage pulsed power supply can be usedto remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It isnovel to apply the magnetic field in removing SO2 as discussed in this paper. The mechanismsof removing sulfur dioxide by non-thermal plasma along with the application of the magneticfield are analyzed, and the related factors affecting the removal efficiency, such as the magnitudeof pulsed voltage, the polarity of the pulse, the layout of the discharge electrode, especially themagnetic field are experimentally investigated. It can be concluded that the purification efficiencyis improved significantly by applying the magnetic field.展开更多
The kinetics mechanism of the dissociation reactions in a NO/SO_2/N_2/O_2 system was investigated in consideration of energetic electrons' impacts on a non-thermal plasma.A model was derived from the Boltzmann equ...The kinetics mechanism of the dissociation reactions in a NO/SO_2/N_2/O_2 system was investigated in consideration of energetic electrons' impacts on a non-thermal plasma.A model was derived from the Boltzmann equation and molecule collision theory to predict the dissociation reaction rate coefficients.Upon comparison with available literature,the model was confirmed to be acceptably accurate in general.Several reaction rate coefficients of the NO/SO_2/N_2/O_2 dissociation system were derived according to the Arrhenius formula.The activation energies of each plasma reaction were calculated by quantum chemistry methods.The relation between the dissociation reaction rate coefficient and electron temperature was established to describe the importance of each reaction and to predict relevant processes of gaseous chemical reactions.The sensitivity of the mechanism of NO/SO_2/N_2/O_2 dissociation reaction in a non-thermal plasma was also analysed.展开更多
In this paper, NiAl layered double hydroxides (NiAl-LDHs) has been modified by non-thermal plasma (NTP) to enhance the fluoride removal capacity of materials. The samples were characterized by X-ray diffraction, Fouri...In this paper, NiAl layered double hydroxides (NiAl-LDHs) has been modified by non-thermal plasma (NTP) to enhance the fluoride removal capacity of materials. The samples were characterized by X-ray diffraction, Fourier transform infrared spectrometer (FTIR), Thermogravimetric differential thermal analyzer (TG-DTA) and N2 adsorption-desorption. Effects of pH, co-existing anions, temperature and kinetics on F﹣ adsorption were investigated. The results showed that pH affects the adsorbent surface charge. The effective pH range for F﹣ removal was between 4.5 and 10. Lower pH potentially causes dissolution of NiAl-LDHs. The negligible interference of coexisting ions such as makes the NiAl-LDHs a promising sorbent for fluoride polluted water treatment.展开更多
A non-thermal plasma brush is employed to deposit stain-resistant SiO2-like coatings on resin composite fillings and bovine teeth.With post-treating by plasma,the hardness of the coating increases from H to 8H and the...A non-thermal plasma brush is employed to deposit stain-resistant SiO2-like coatings on resin composite fillings and bovine teeth.With post-treating by plasma,the hardness of the coating increases from H to 8H and the water contact angle decreases from 98.8° to 61.7°.The Fourier transform infrared spectroscopy (FTIR) results show that,after plasma post-treating,the Si-O-Si and Si-OH bonds of the coating increase.Scanning electron microscope (SEM) images show the coatings to be uniform,without cracks.The coatings present outstanding performance in a stain resistance test both on resin composite and bovine teeth.Being easy to handle and less time consuming than traditional methods,with a body-friendly temperature and material,this plasma brush provides a promising in-situ coating method on patient teeth in dental clinics.展开更多
A typical quinolones antibiotic ciprofloxacin(CIP) in aqueous solution was degraded by a gas–liquid discharge non-thermal plasma system. The discharge plasma power and the emission intensity of the excited reactive s...A typical quinolones antibiotic ciprofloxacin(CIP) in aqueous solution was degraded by a gas–liquid discharge non-thermal plasma system. The discharge plasma power and the emission intensity of the excited reactive species(RS) generated in the gas phase were detected by the oscilloscope and the optical emission spectroscopy. The effects of various parameters on CIP degradation, i.e. input powers, initial concentrations addition of radical scavengers and p H values were investigated. With the increase of discharge power, the degradation efficiency increased but the energy efficiency significantly reduced. The degradation efficiency also reduced under high concentration of initial CIP conditions due to the competitive reactions between the plasma-induced RS with the degradation intermediates of CIP. Different radical scavengers(isopropanol and CCl_4) on ·OH and H· were added into the reaction system and the oxidation effects of ·OH radicals have been proved with high degradation capacity on CIP.Moreover, the long-term degradation effect on CIP in the plasma-treated aqueous solution proved that the long-lived RS(H_2O_2 and O_3, etc) might play key roles on the stay effect through multiple aqueous reactions leading to production of ·OH. The degradation intermediates were determined by the method of electrospray ionization(+)-mass spectroscopy, and the possible degradation mechanism were presented.展开更多
基金supported by the National Key Research and Development Program of China(No.2018YFC1903100)Beijing Municipal Science and Technology Project Program(No.Z191100009119002)the State Environmental Protection Key Laboratory of Odor Pollution Control(No.20210504)。
文摘Non-thermal plasma(NTP)is considered to be a promising technology for the removal of volatile organic compounds;however,its application is limited by low CO_(2) selectivity and undesirable by-products.To overcome these issues,this paper discusses the degradation of chlorobenzene(CB)in systems of NTP coupled with catalysts,and the influence of catalyst locations in the NTP was investigated.In addition,the interaction between plasma and catalyst was also explored.The results indicated that the degradability of CB was remarkably improved through the combination of NTP with catalysts,and the formation of ozone was effectively inhibited.The degradation efficiency increased from 33.9%to 79.6%at 14 kV in the NTPcatalytic system,while the ozone concentration decreased from 437 to 237 mg m^(-3),and the degradation efficiency of in plasma catalysis(IPC)systems was superior to that of the post plasma catalysis system,while the inhibition ability of ozone exhibited an opposing trend.In the IPC system,the degradation efficiency was 87.7%at 14 k V,while the ozone concentration was151 mg m^(-3).Besides,the plasma did not destroy the pore structure and crystal structure of the catalyst,but affected the surface morphology and redox performance of the catalyst.Thus,NTP coupled catalytic system could improve the degradation performance of CB.Furthermore,the plasma discharge characteristics played a major role in the NTP synergistic catalytic degradation of CB.Finally,based on the experiment analysis results,the general reaction mechanism of CB degradation in an IPC reaction system was proposed.
基金the financial support from the Jiangsu Specially-Appointed Professors Program and the European Commission under the Marie Skłodowska-Curie Individual Fellowship(H2020-MSCA-IFNTPleasure-748196).
文摘C1 chemistrymainly involves the catalytic transformation of C1molecules(i.e.,CO,CO2,CH4 and CH3OH),which usually encounters thermodynamic and/or kinetic limitations.To address these limitations,non-thermal plasma(NTP)activated heterogeneous catalysis offers a number of advantages,such as relatively mild reaction conditions and energy efficiency,in comparison to the conventional thermal catalysis.This review presents the state-of-the-art for the application of NTP-catalysis towards C1 chemistry,including the CO2 hydrogenation,reforming of CH4 and CH3OH,and water-gas shift(WGS)reaction.In the hybrid NTP-catalyst system,the plasma-catalyst interactions aremultifaceted.Accordingly,this reviewalso includes a brief discussion on the fundamental research into themechanisms of NTP activated catalytic C1 chemistry,such as the advanced characterisation methods(e.g.,in situ diffuse reflectance infrared Fourier transform spectroscopy,DRIFTS),temperatureprogrammed plasma surface reaction(TPPSR),kinetic studies.Finally,prospects for the future research on the development of tailor-made catalysts for NTP-catalysis systems(which will enable the further understanding of its mechanism)and the translation of the hybrid technique to practical applications of catalytic C1 chemistry are discussed.
基金supported by National Natural Science Foundation of China(No.51806085)China Postdoctoral Science Foundation(No.2018M642175)+2 种基金Jiangsu Planned Projects for Postdoctoral Research Fund(No.2018K101C)Open Research Subject of Key Laboratory of automotive measurement,control and safety(Xihua University)(No.QCCK2021-007)Graduate Student Innovation Fund Project of Jiangsu Province(No.KYCX213354)。
文摘Particulate matter(PM)capture tests were carried out on clean diesel particulate filters(DPFs)under different loads(25%,50%,75%and 100%).DPFs were regenerated by a non-thermal plasma(NTP)injection device.Raman spectroscopy and x-ray photoelectron spectroscopy were used to investigate changes in the microstructure and element occurrence state of the sediment in DPF channel before and after regeneration.The order of the PM samples decreased before NTP treatment as the load increased;the amorphous carbon content was high,and the oxidationactivity was higher.After NTP treatment,the carbon atoms at the edge of the microcrystalline structure in the ash-PM samples were oxidized,and the structure was reorganized;in addition,the amorphous carbon content decreased,and the structure was more diversified.Before NTP,the C element of PM samples was the main component,and the content of the O element was relatively low.The C element occurred in the form of C–C,C–OH,and O–C=O functional groups,and O atoms were mainly combined with C–O.After NTP,the content of Na,P,S,Ca,and other inorganic elements in ash-PM samples was prominent because C atoms were removed by NTP active substances.There were two forms of S element occurrence(SO42-and SO32-);the proportion of SO42-was approximately 40%,and the proportion of SO32-was approximately60%.Study of the microstructure and element occurrence of the residues in the DPF channels improved our understanding of the mechanism of the low-temperature regeneration of DPFfrom NTP.
基金supported by grants from the IIT Delhi FIRP program grant (No. MI02081)
文摘Non-thermal plasma has emerged as an effective treatment system against the latest class of highly recalcitrant and toxic environmental pollutants termed emerging contaminants(ECs).In the present work,a detailed experimental study is carried out to evaluate the efficacy of a non-thermal plasma jet with two dyes,Rd.B and Met.Blue,as model contaminants.The plasma jet provided a complete dye decoloration in 30 min with an applied voltage of 6.5 kV_(p-p).·OH,having the highest oxidation potential,acts as the main reactive species,which with direct action on contaminants also acts indirectly by getting converted into H_(2)O_(2)and O_(3).Further,the effect of critical operational parameters viz,sample pH,applied voltage(4.5–6.5 kV_(p-p)),conductivity(5–20 mS cm^(-1)),and sample distance on plasma treatment efficacy was also examined.Out of all the assessed parameters,the applied voltage and sample conductivity was found to be the most significant operating parameters.A high voltage and low conductivity favored the dye decoloration,while the pH effect was not that significant.To understand the influence of plasma discharge gas on treatment efficacy,all the experiments are conducted with argon and helium gases under the fixed geometrical configuration.Both the gases provided a similar dye decoloration efficiency.The DBD plasma system with complete dye removal also rendered maximum mineralization of 73%for Rd.B,and 60%for Met.Blue.Finally,the system's efficiency against the actual ECs(four pharmaceutical compounds,viz,metformin,atenolol,acetaminophen,and ranitidine)and microbial contaminant(E.coli)was also tested.The system showed effectivity in the complete removal of targeted pharmaceuticals and a log2.5 E.coli reduction.The present systematic characterization of dye degradation could be of interest to large communities working towards commercializing plasma treatment systems.
基金supported by National Natural Science Foundation of China(Nos.11605159 and 11405147)Chinese Postdoctoral Science Foundation(No.2017M612412)+3 种基金the Foundation of Key Technology Research Project of Henan Province(No.182102311115)Key Discipline Construction Project of Zhengzhou University(No.32410257)Youth Innovation Project of Key Discipline of Zhengzhou University(No.XKZDQN202002)Natural Science Foundation of Henan Province(No.202300410013)。
文摘Mung bean(Vigna radiata)sprouts are widely consumed worldwide due to their high nutritional value.However,the low yield and microbial contamination of mung bean sprouts seriously reduces their economic value.This study investigates the effects of non-thermal plasma on the quality and microbial reduction of mung bean sprouts by pretreatment of seeds in water for different times(0,1,3 and 6 min).The quality results showed that short-time plasma treatment(1 and 3 min)promoted seed germination and seedling growth,whereas long-time plasma treatment(6 min)had inhibitory effects.Plasma also had a similar dose effects on the total flavonoid and phenolic contents of mung bean sprouts.The microbiological results showed that plasma treatment achieved a reduction of native microorganisms ranging from 0.54 to 7.09 log for fungi and 0.29 to 6.80 log for bacteria at 96 h incubation.Meanwhile,plasma treatment could also efficiently inactivate artificially inoculated Salmonella typhimurium(1.83–6.22 log)and yeast(0.53–3.19 log)on mung bean seeds.The results of seed coat permeability tests and scanning electron microscopy showed that plasma could damage the seed coat structure,consequently increasing the electrical conductivity of mung bean seeds.The physicochemical analysis of plasma-treated water showed that plasma generated various long-and short-lived active species[nitric oxide radicals(NO·),hydroxyl radicals(·OH),singlet oxygen(1O2),hydrogen peroxide(H_(2)O_(2)),nitrate(NO_(3)^(-)),and nitrite(NO_(2)^(-))]in water,thus the oxidizability,acidity and conductivity of plasma-treated water were all increased in a treatment timedependent manner.The result for mimicked chemical mixtures confirmed the synergistic effect of activity of H_(2)O_(2),NO_(3)^(-)and NO_(2)^(-)on bacterial inactivation and plant growth promotion.Taken together,these results imply that plasma pretreatment of mung bean seeds in water with moderate oxidizability and acidity is an effective method to improve the yield of mung bean sprouts and reduce microbial contamination.
基金supported by National Key Research and Development Project of China(No.2019YFC1805503)National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2019A13)+1 种基金the Open Project Program of the State Key Laboratory of Petroleum Pollution Control(No.PPC2019013)Major Science and Technology Projects of Shanxi Province(No.20181102017)。
文摘The presented work reports the selective catalytic reduction(SCR)of NO_(x) assisted by dielectric barrier discharge plasma via simulating marine diesel engine exhaust,and the experimental results demonstrate that the low-temperature activity of NH_(3)-SCR assisted by non-thermal plasma is enhanced significantly,particularly in the presence of a C_(3)H_(6) additive.Simultaneously,CeMnZrO_(x)@TiO_(2) exhibits strong tolerance to SO_(2) poisoning and superior catalytic stability.It is worthwhile to explore a new approach to remove NO_(x) from marine diesel engine exhaust,which is of vital significance for both academic research and practical applications.
基金by the National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2019A13)the National Key Research and Development Project of China(No.2019YFC1805505)+2 种基金the Shanxi Province Bidding Project(No.20191101007)the Major Science and Technology Projects of Shanxi Province(No.20181102017)State Key Laboratory of Organic Geochemistry(No.SKLOG-201909)。
文摘NOx storage and reduction(NSR)technology has been regarded as one of the most promising strategies for the removal of nitric oxides(NOx)from lean-burn engines,and the potential of the plasma catalysis method for NOx reduction has been confirmed in the past few decades.This work reports the NSR of nitric oxide(NO)by combining non-thermal plasma(NTP)and Co/Pt/Ba/γ-Al2O3(Co/PBA)catalyst using methane as a reductant.The experimental results reveal that the NOx conversion of NSR assisted by NTP is notably enhanced compared to the catalytic efficiency obtained from NSR in the range of 150°C–350°C,and NOx conversion of the 8%Co/PBA catalyst reaches 96.8%at 350°C.Oxygen(O_(2))has a significant effect on the removal of NOx,and the NOx conversion increases firstly and then decreases when the O_(2)concentration ranges from 2%to 10%.Water vapor reduces the NOx storage capacity of Co/PBA catalysts on account of the competition for adsorption sites on the surface of Co/PBA catalysts.There is a negative correlation between sulfur dioxide(SO_(2))and NOx conversion in the NTP system,and the 8%Co/PBA catalyst exhibits higher NOx conversion compared to other catalysts,which shows that Co has a certain SO_(2)resistance.
基金The National Basic Research Program(973) of China(G1999022209)
文摘An experimental system of De-NO with plasma-catalyst（Cu zeolite） was established to investigate the differences between De-NO with plasma-catalyst and De-NO only with plasma, to provide the instruction for selecting appropriate catalyst and operating condition. The characteristics of De-NO with plasma and De-NO with plasma-catalyst were investigated comparatively by experiments. The experimental results show that De-NO with plasma-catalyst has high NO removal rate; Cu zeolite is an effective catalyst which can promote NO removal rate in plasma remarkably; De-NO with plasma-catalyst should be operated at low temperature and the temperature has opposite effects on the function of catalyst and plasma; water vapor and O2 can increase the NO removal rate.
基金supported by Anhui University of Science and Technology Youth Fund(No.QN201415)Anhui Province Science and Technology Key Project(No.1301042130)College Students’ Innovation and Entrepreneurship Training Program(No.201810361079)
文摘In this work,non-thermal plasma has been applied to treat polyacrylamide(PAM)wastewater.We have investigated the in fluence of the rule of PAM wastewater initial pH,solution concentration and discharge time,discharge voltage on chemical oxygen demand(COD)degradation rate.At the same time,the effect of pH and discharge time on the viscosity removal rate of PAM solution was also studied.Then,the effect of pH on the viscosity removal rate of 1.0g 1^-1 PAM solution was studied separately.Through orthogonal test,the factors affecting the COD degradation rate of PAM wastewater were determined as follows:discharge time>discharge voltage>solution concentration>wastewater initial pH.1'he COD highest removal rate of PAM wastewater reached 85.74%,when the optimal conditions are as follows:discharge voltage 40 kV,discharge time 5 h,solution concentration 1.0 g 1^-1,pH 1.5.This research provides some basic data and new theoretical basis for PAM wastewater purification.
基金supported by grants from the National Natural Sciences Foundation of China(Nos.10875048,30700717)
文摘The present study evaluated the effect of non-thermal plasma on skin wound healing in BalB/c mice.Two 6-mm wounds along the both sides of the spine were created on the back of each mouse(n=80) by using a punch biopsy.The mice were assigned randomly into two groups,with 40 animals in each group:a non-thermal plasma group in which the mice were treated with the non-thermal plasma;a control group in which the mice were left to heal naturally.Wound healing was evaluated on postoperative days(POD) 4,7,10 and 14(n=5 per group in each POD) by percentage of wound closure.The mice was euthanized on POD 1,4,7,10,14,21,28 and 35(n=1 in each POD).The wounds were removed,routinely fixed,paraffin-embedded,sectioned and HE-stained.A modified scoring system was used to evaluate the wounds.The results showed that acute inflammation peaked on POD 4 in non-thermal plasma group,earlier than in control group in which acute inflammation reached a peak on POD 7,and the acute inflammation scores were much lower in non-thermal group than in control group on POD 7(P<0.05).The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group(P<0.05).The re-epithelialization score and the neovasularization score were increased significantly in non-thermal group when compared with control group on POD 7 and 10(P<0.05 for all).The count of bacterial colonies was 103 CFU/mL on POD 4 and <20 CFU/mL on POD 7,significantly lower than that in control group(109 CFU/mL on POD 4 and >1012 CFU/mL on the POD 7)(P<0.05).It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colonization.
基金financially supported by National Natural Science Foundation of China (Nos.11505013,11775028)Beijing Municipal Excellent Talent Training Foundation (No.2016000026833ZK12)+2 种基金Science and Technology Innovational Serviceability Building Project of Beijing Municipal Education Commission (No.PXM2017_014223_000066)Excellent Talent Selection and Training Project of BIGC of China (No.04190117004/026)Institute level project of BIGC of China (No.Eb201502)
文摘This review describes the application of non-thermal plasma(NTP) technology for high barrier layer fabrication in packaging area.NTP technology is considered to be the most prospective approaches for the barrier layer fabrication over the past decades due to unpollution,high speed,low-costing.The applications of NTP technology have achieved numerous exciting results in high barrier packaging area.Now it seemly demands a detailed review to summarize the past works and direct the future developments.This review focuses on the different NTP resources applied in the high barrier area,the role of plasma surface modification on packaging film surface properties,and the deposition of different barrier coatings based on NTP technology.In particular,this review emphasizes the cutting-edge technologies of NTP on interlayer deposition with organic,inorganic for multilayer barriers fabrication.The future prospects of NTP technology in high barrier film areas are also described.
基金supported by National Natural Science Foundation of China (Nos.10835004 and 10905010)the New Century Excellent Talents in University of China (No.NCET-08-0760)
文摘An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus (S. aureus). The plasma jet was generated by dielectric barrier discharge (DBD), which was characterized by electrical and optical diagnostics. The survival curves of the bacteria showed that the plasma jet could effectively inactivate 10 6 cells of S. aureus within 120 seconds and the sterilizing efficiency depended critically on the discharge parameter of the applied voltage. It was further confirmed by scanning electron microscopy (SEM) that the cell morphology was seriously damaged by the plasma treatment. The plasma sterilization mechanism of S. aureus was attributed to the active species of OH, N 2 + and O, which were generated abundantly in the plasma jet and characterized by OES. Our findings suggest a convenient and low-cost way for sterilization and inactivation of bacteria.
基金supported by National Natural Science Foundation of China(No.51176001)
文摘In this paper,the characteristics of detonation combustion ignited by AC-driven non-thermal plasma and spark plug in air/acetylene mixture have been compared in a doubletube experiment system.The two tubes had the same structure,and their closed ends were installed with a plasma generator and a spark plug,respectively.The propagation characteristics of the flame were measured by pressure sensors and ion probes.The experiment results show that,compared with a spark plug,the non-thermal plasma obviously broadened the range of equivalence ratio when the detonation wave could develop successfully,it also heightened the pressure value of detonation wave.Meanwhile,the detonation wave development time and the entire flame propagation time were reduced by half.All of these advantages benefited from the larger ignition volume when a non-thermal plasma was applied.
基金supported by the Science Foundation for the Excellent Doctor Dissertations of Ministry of Education of China (No. 200338)the State Natural Sciences Foundation of China (Nos. 50937004, 50777051)
文摘Improvement of polytetrafluoroethylene surface energy by non-thermal plasma treatmentis presented,using a nanosecond-positive-edge repetitive pulsed dielectric barrier dischargegenerator in atmospheric air.The electrical parameters including discharging power,peak anddensity of micro-discharge current were calculated,and the electron energy was estimated.Surfacetreatment experiments of polytetrafluoroethylene films were conducted for both differentapplied voltages and different treating durations.Results show that the surface energy of polytetrafluoroethylenefilm could be improved to 40 mJ/m^2 or more by plasma treatment.Surfaceroughness measurement and surface X-ray photoelectron spectroscopy analysis indicate that thereare chemical etching and implantation of polar oxygen groups in the sample surface treating process,resulting in the improvement of the sample surface energy.Compared with an AC sourceof 50 Hz,the dielectric barrier discharges generated by a repetitive pulsed source could providehigher peak power,lower mean power,larger micro-discharge current density and higher electronenergy.Therefore,with the same applied peak voltage and treating duration,the improvementof polytetrafluoroethylene surface energy using repetitive pulsed plasma is more effective,and theplasma treatment process based on repetitive pulsed dielectric barrier discharges in air is thusfeasible and applicable.
基金The project supported by the Teaching and Research Award Program for Outstanding Young Teachers in Higher EducationInstitutions under the MOE, China (No. 123-2002)
文摘The non-thermal plasma created by high voltage pulsed power supply can be usedto remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It isnovel to apply the magnetic field in removing SO2 as discussed in this paper. The mechanismsof removing sulfur dioxide by non-thermal plasma along with the application of the magneticfield are analyzed, and the related factors affecting the removal efficiency, such as the magnitudeof pulsed voltage, the polarity of the pulse, the layout of the discharge electrode, especially themagnetic field are experimentally investigated. It can be concluded that the purification efficiencyis improved significantly by applying the magnetic field.
文摘The kinetics mechanism of the dissociation reactions in a NO/SO_2/N_2/O_2 system was investigated in consideration of energetic electrons' impacts on a non-thermal plasma.A model was derived from the Boltzmann equation and molecule collision theory to predict the dissociation reaction rate coefficients.Upon comparison with available literature,the model was confirmed to be acceptably accurate in general.Several reaction rate coefficients of the NO/SO_2/N_2/O_2 dissociation system were derived according to the Arrhenius formula.The activation energies of each plasma reaction were calculated by quantum chemistry methods.The relation between the dissociation reaction rate coefficient and electron temperature was established to describe the importance of each reaction and to predict relevant processes of gaseous chemical reactions.The sensitivity of the mechanism of NO/SO_2/N_2/O_2 dissociation reaction in a non-thermal plasma was also analysed.
文摘In this paper, NiAl layered double hydroxides (NiAl-LDHs) has been modified by non-thermal plasma (NTP) to enhance the fluoride removal capacity of materials. The samples were characterized by X-ray diffraction, Fourier transform infrared spectrometer (FTIR), Thermogravimetric differential thermal analyzer (TG-DTA) and N2 adsorption-desorption. Effects of pH, co-existing anions, temperature and kinetics on F﹣ adsorption were investigated. The results showed that pH affects the adsorbent surface charge. The effective pH range for F﹣ removal was between 4.5 and 10. Lower pH potentially causes dissolution of NiAl-LDHs. The negligible interference of coexisting ions such as makes the NiAl-LDHs a promising sorbent for fluoride polluted water treatment.
文摘A non-thermal plasma brush is employed to deposit stain-resistant SiO2-like coatings on resin composite fillings and bovine teeth.With post-treating by plasma,the hardness of the coating increases from H to 8H and the water contact angle decreases from 98.8° to 61.7°.The Fourier transform infrared spectroscopy (FTIR) results show that,after plasma post-treating,the Si-O-Si and Si-OH bonds of the coating increase.Scanning electron microscope (SEM) images show the coatings to be uniform,without cracks.The coatings present outstanding performance in a stain resistance test both on resin composite and bovine teeth.Being easy to handle and less time consuming than traditional methods,with a body-friendly temperature and material,this plasma brush provides a promising in-situ coating method on patient teeth in dental clinics.
基金financially supported by National Natural Science Foundation of China (Nos. 51777206 and 51541807)Natural Science Foundation of Anhui Province (Nos. 1708085MB47 and 1708085MA13)+2 种基金Foundation of Anhui Province Key Laboratory of Medical Physics and Technology (No. LMPT2017Y7BP0U1581)Doctoral Fund of Ministry of Education of China (No. 2017M612058)Specialized Research Fund for the Doctoral Program of Hefei University of Technology (Nos. JZ2016HGBZ0768, JZ2016HGBZ0769, and JZ2017HGBZ0944)
文摘A typical quinolones antibiotic ciprofloxacin(CIP) in aqueous solution was degraded by a gas–liquid discharge non-thermal plasma system. The discharge plasma power and the emission intensity of the excited reactive species(RS) generated in the gas phase were detected by the oscilloscope and the optical emission spectroscopy. The effects of various parameters on CIP degradation, i.e. input powers, initial concentrations addition of radical scavengers and p H values were investigated. With the increase of discharge power, the degradation efficiency increased but the energy efficiency significantly reduced. The degradation efficiency also reduced under high concentration of initial CIP conditions due to the competitive reactions between the plasma-induced RS with the degradation intermediates of CIP. Different radical scavengers(isopropanol and CCl_4) on ·OH and H· were added into the reaction system and the oxidation effects of ·OH radicals have been proved with high degradation capacity on CIP.Moreover, the long-term degradation effect on CIP in the plasma-treated aqueous solution proved that the long-lived RS(H_2O_2 and O_3, etc) might play key roles on the stay effect through multiple aqueous reactions leading to production of ·OH. The degradation intermediates were determined by the method of electrospray ionization(+)-mass spectroscopy, and the possible degradation mechanism were presented.
