Cu-based materials are ideal catalysts for CO_(2) electrocatalytic reduction reaction(CO_(2)RR) into multicarbon products.However,such reactions require stringent conditions on local environments of catalyst surfaces,...Cu-based materials are ideal catalysts for CO_(2) electrocatalytic reduction reaction(CO_(2)RR) into multicarbon products.However,such reactions require stringent conditions on local environments of catalyst surfaces,which currently are the global pressing challenges.Here,a stabilized activation of Cu^(0)/Cu^(+)-onAg interface by N_(2) cold plasma treatment was developed for improving Faradaic efficiency(FE) of CO_(2)RR into C2 products.The resultant Ag@Cu-CuN_x exhibits a C2 FE of 72% with a partial current density of-14.9 mA cm^(-2) at-1.0 V vs.RHE(reversible hydrogen electrode).Combining density functional theory(DFT) and experimental investigations,we unveiled that Cu^(0)/Cu^(+) species can be co ntrollably tu ned by the incorporation of nitrogen to form CuN_x on Ag surface,i.e.,Ag@Cu-CuN_x.This strategy enhances ^(*)CO intermediates generation and accelerates C-C coupling both thermodynamically and kinetically.The intermediates O^(*)C^(*)CO,^(*)COOH,and ^(*)CO were detected by in-situ attenuated total internal reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS).The uncovered CO_(2)RR-into-C2 products were carried out along CO_(2)→^(*)COOH→^(*)CO→O^(*)C^(*)CO→^(*)C_(2)H_(3)O→^(*)C_(2)H_(4)O→ C_(2)H_(5)OH(or ^(*)C_(2)H_(3)O→^(*)O+C_(2)H_(4)) paths over Ag@Cu-CuN_x electrocatalyst.This work provides a new approach to design Cu-based electrocatalysts with high-efficiency,mild condition,and stable CO_(2)RR to C2 products.展开更多
Hepatitis C virus(HCV) is the leading indication for liver transplantation in the United States.It recurs universally after transplant but the rate of fibrosis and the development of graft failure is variable.Differen...Hepatitis C virus(HCV) is the leading indication for liver transplantation in the United States.It recurs universally after transplant but the rate of fibrosis and the development of graft failure is variable.Different donor and recipient features have been demonstrated to impact fibrosis.Plasma cell hepatitis,a histologic finding,is one feature associated with poor graft and patient outcomes.The pathogenic mechanism resulting in plasma cell hepatitis is poorly understood,with evidence suggesting a role for both the HCV and the immune system.A recent publication described plasma cell hepatitis in a larger context of immune medicated graft dysfunction in transplant recipients receiving interferon based therapy.This manuscript will highlight the topic of plasma cell hepatitis and provide commentary on the lack of recognition,the data regarding pathophysiologic mechanisms and the potential management options.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 biops...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（P0.05）.The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group（P0.05）.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（P0.05 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）（P0.05）.It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colo-nization.展开更多
In order to prepare high quality Mo（Si,Al）2 feedstock characterized with C40 phase, higher Al doping amount andexcellent flowability, Mo（Si1-x,Alx）2 with different Al contents （x=0, 0.1, 0.2, 0.3, 0.4, 0.5） were...In order to prepare high quality Mo（Si,Al）2 feedstock characterized with C40 phase, higher Al doping amount andexcellent flowability, Mo（Si1-x,Alx）2 with different Al contents （x=0, 0.1, 0.2, 0.3, 0.4, 0.5） were synthesized by self-propagatinghigh-temperature synthesis first and Mo（Si0.6,Al0.4）2 was confirmed as the suitable material through X-ray diffraction analysis. Aseries of tests with different parameters of induction plasma spheroidization were applied to improving the flowability of feedstock.Mo（Si,Al）2 feedstock with excellent flowability （26.2 s/50 g） was prepared through adding hydrogen into sheath gas and decreasingthe powder feeding rate. The composition segregation occurred in the spheroidized powder after Al consumption and oxidation. Theinhomogeneous structure of the same particle was caused by the asymmetric heating and cooling when particle passed through theplasma jet.展开更多
The IR emission spectra of methane were measured under DC glow discharge conditions. The distinct difference in time between methane decomposition and C2 hydrocarbons formation was specially pointed out. Ca hydrocarbo...The IR emission spectra of methane were measured under DC glow discharge conditions. The distinct difference in time between methane decomposition and C2 hydrocarbons formation was specially pointed out. Ca hydrocarbons formed at the end of methane decomposition. The optimum condition for C2 hydrocarbon formation was studied and the optimum combination between electric current density and methane input quantity was suggested. The appropriate reaction conditions for methane decomposition and Ca hydrocarbons formation are different, so high yield of Ca hydrocarbons will be probably obtained when different conditions are taken.展开更多
The plasma technology served as a tool in unconventional catalysis has been used in natural gas conversion,because the traditional catalytic methane oxidative coupling reaction must be performed at high temperature on...The plasma technology served as a tool in unconventional catalysis has been used in natural gas conversion,because the traditional catalytic methane oxidative coupling reaction must be performed at high temperature on account of the stability of methane molecule.The focus of this research is to develop a process of converting methane to C2 hydrocarbons with non-equilibrium plasma technology at room temperature and atmospheric pressure.It was found that methane conversion increased and the selectivity of C2 hydrocarbons decreased with the voltage.The optimum input voltage range was 40-80 V corresponding to high yield of C2 hydrocarbons.Methane conversion decreased and the selectivity of C2 hydrocarbons increased with the inlet flow rate of methane.The proper methane flow rate was 20-40 ml/min （corresponding residence time 10-20 s）.The experimental results show that methane conversion was 47% and the selectivity of C2 hydrocarbons was 40% under the proper condition using atmospheric DBD cold plasma technology.It was found that the breakdown voltage of methane VB was determined by the type of electrode and the discharge gap width in this glow discharge reactor.The breakdown voltage of methane VB,min derived from the Paschen law equation was established.展开更多
Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel.Plasma nitrocarburizing was conducted for 12 h at 540℃in the nitrogen, hydrogen and ...Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel.Plasma nitrocarburizing was conducted for 12 h at 540℃in the nitrogen, hydrogen and methane atmosphere to produce theε-Fe-（2-3）（N,C） phase.The compound layer produced by plasma nitrocarburising was predominantly composed ofε-phase,with a small proportion ofγ′-Fe-4 （N,C） phase. The thickness of the compound layer and the diffusion layer are about 10μm and about 200μm,respectively. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of 500℃for 1 h.The very thin magnetite （Fe-3O-4） layer of 1-2μm in thickness on top of the compound layer was obtained.Anodic polarization test revealed that plasma nitrocarburizing process contributed a significant improvement of corrosion resistance of SKD 61 steel.However,the corrosion characteristics of the nitrocarburized compound layer was deteriorated by oxidation treatment.展开更多
Ultrafine Ti(C,N)-based cermet was sintered by SPS from 1050℃ to 1450℃ and its sintering properties,such as porosity,mechanical properties and phase transformation,were investigated by optical microscopy (OM),scanni...Ultrafine Ti(C,N)-based cermet was sintered by SPS from 1050℃ to 1450℃ and its sintering properties,such as porosity,mechanical properties and phase transformation,were investigated by optical microscopy (OM),scanning electron microscopy (SEM),X-ray diffraction (XRD),and differential scanning calorimeter (DSC).It is found that the spark plasma sintering properties of Ti(C,N)-based cermet differ from those of conventional vacuum sintering.The liquid phase appearance is at least lower by 150℃ than that in vacuum sintering.The porosity decreases sharply below 1 200℃ and reaches minimum at 1 200℃,and afterwards it almost keeps invariable and no longer increases.SPS remarkably accelerates the phase transformation of Ti(C,N)-based cermet and it has a powerful ability to remove oxides in Ti(C,N)-based cermets.Above 1 350℃,denitrification occurred.Fresh graphite phase formed above 1 430℃.Both the porosity and graphite are responsible for the poor TRS.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
基金the National Natural Science Foundation of China (21902017)the Foundation of technological innovation and application development of Chongqing (cstc2021jscxmsxm X0308, CSTB2022BSXM-JCX0132)+1 种基金the Youth project of science and technology research program of Chongqing Education Commission of China (KJQN20211107)the Scientific Research Foundation of Chongqing University of Technology (2020ZDZ022, 2021PYZ13)。
文摘Cu-based materials are ideal catalysts for CO_(2) electrocatalytic reduction reaction(CO_(2)RR) into multicarbon products.However,such reactions require stringent conditions on local environments of catalyst surfaces,which currently are the global pressing challenges.Here,a stabilized activation of Cu^(0)/Cu^(+)-onAg interface by N_(2) cold plasma treatment was developed for improving Faradaic efficiency(FE) of CO_(2)RR into C2 products.The resultant Ag@Cu-CuN_x exhibits a C2 FE of 72% with a partial current density of-14.9 mA cm^(-2) at-1.0 V vs.RHE(reversible hydrogen electrode).Combining density functional theory(DFT) and experimental investigations,we unveiled that Cu^(0)/Cu^(+) species can be co ntrollably tu ned by the incorporation of nitrogen to form CuN_x on Ag surface,i.e.,Ag@Cu-CuN_x.This strategy enhances ^(*)CO intermediates generation and accelerates C-C coupling both thermodynamically and kinetically.The intermediates O^(*)C^(*)CO,^(*)COOH,and ^(*)CO were detected by in-situ attenuated total internal reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS).The uncovered CO_(2)RR-into-C2 products were carried out along CO_(2)→^(*)COOH→^(*)CO→O^(*)C^(*)CO→^(*)C_(2)H_(3)O→^(*)C_(2)H_(4)O→ C_(2)H_(5)OH(or ^(*)C_(2)H_(3)O→^(*)O+C_(2)H_(4)) paths over Ag@Cu-CuN_x electrocatalyst.This work provides a new approach to design Cu-based electrocatalysts with high-efficiency,mild condition,and stable CO_(2)RR to C2 products.
文摘Hepatitis C virus(HCV) is the leading indication for liver transplantation in the United States.It recurs universally after transplant but the rate of fibrosis and the development of graft failure is variable.Different donor and recipient features have been demonstrated to impact fibrosis.Plasma cell hepatitis,a histologic finding,is one feature associated with poor graft and patient outcomes.The pathogenic mechanism resulting in plasma cell hepatitis is poorly understood,with evidence suggesting a role for both the HCV and the immune system.A recent publication described plasma cell hepatitis in a larger context of immune medicated graft dysfunction in transplant recipients receiving interferon based therapy.This manuscript will highlight the topic of plasma cell hepatitis and provide commentary on the lack of recognition,the data regarding pathophysiologic mechanisms and the potential management options.
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（P0.05）.The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group（P0.05）.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（P0.05 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）（P0.05）.It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colo-nization.
基金Project (20101101120030) supported by International Graduate Exchange Program of Beijing Institute of Technologysupported by the Research Fund for the doctoral Program of Higher Education of China
文摘In order to prepare high quality Mo（Si,Al）2 feedstock characterized with C40 phase, higher Al doping amount andexcellent flowability, Mo（Si1-x,Alx）2 with different Al contents （x=0, 0.1, 0.2, 0.3, 0.4, 0.5） were synthesized by self-propagatinghigh-temperature synthesis first and Mo（Si0.6,Al0.4）2 was confirmed as the suitable material through X-ray diffraction analysis. Aseries of tests with different parameters of induction plasma spheroidization were applied to improving the flowability of feedstock.Mo（Si,Al）2 feedstock with excellent flowability （26.2 s/50 g） was prepared through adding hydrogen into sheath gas and decreasingthe powder feeding rate. The composition segregation occurred in the spheroidized powder after Al consumption and oxidation. Theinhomogeneous structure of the same particle was caused by the asymmetric heating and cooling when particle passed through theplasma jet.
基金Supported by the Special Fund of the Education Committee of Shaanxi Province (No. 2000K13-G19 and No. 2002K09-G21).
文摘The IR emission spectra of methane were measured under DC glow discharge conditions. The distinct difference in time between methane decomposition and C2 hydrocarbons formation was specially pointed out. Ca hydrocarbons formed at the end of methane decomposition. The optimum condition for C2 hydrocarbon formation was studied and the optimum combination between electric current density and methane input quantity was suggested. The appropriate reaction conditions for methane decomposition and Ca hydrocarbons formation are different, so high yield of Ca hydrocarbons will be probably obtained when different conditions are taken.
基金supported by the Research Foundation of SINOPEC under the Grant No. 404003the Research Foundation of Tianjin Scientific & Technology Committee under the Grant No. 043182611
文摘The plasma technology served as a tool in unconventional catalysis has been used in natural gas conversion,because the traditional catalytic methane oxidative coupling reaction must be performed at high temperature on account of the stability of methane molecule.The focus of this research is to develop a process of converting methane to C2 hydrocarbons with non-equilibrium plasma technology at room temperature and atmospheric pressure.It was found that methane conversion increased and the selectivity of C2 hydrocarbons decreased with the voltage.The optimum input voltage range was 40-80 V corresponding to high yield of C2 hydrocarbons.Methane conversion decreased and the selectivity of C2 hydrocarbons increased with the inlet flow rate of methane.The proper methane flow rate was 20-40 ml/min （corresponding residence time 10-20 s）.The experimental results show that methane conversion was 47% and the selectivity of C2 hydrocarbons was 40% under the proper condition using atmospheric DBD cold plasma technology.It was found that the breakdown voltage of methane VB was determined by the type of electrode and the discharge gap width in this glow discharge reactor.The breakdown voltage of methane VB,min derived from the Paschen law equation was established.
文摘Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel.Plasma nitrocarburizing was conducted for 12 h at 540℃in the nitrogen, hydrogen and methane atmosphere to produce theε-Fe-（2-3）（N,C） phase.The compound layer produced by plasma nitrocarburising was predominantly composed ofε-phase,with a small proportion ofγ′-Fe-4 （N,C） phase. The thickness of the compound layer and the diffusion layer are about 10μm and about 200μm,respectively. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of 500℃for 1 h.The very thin magnetite （Fe-3O-4） layer of 1-2μm in thickness on top of the compound layer was obtained.Anodic polarization test revealed that plasma nitrocarburizing process contributed a significant improvement of corrosion resistance of SKD 61 steel.However,the corrosion characteristics of the nitrocarburized compound layer was deteriorated by oxidation treatment.
基金FundedbytheNationalNaturalScienceFoundationofChi na (No .5 0 0 74 0 17)andStateKeyLaboratoryofAdvancedTechnol ogyforMaterialsSynthesisandProcessingofWuhanUniversityofTechnology
文摘Ultrafine Ti(C,N)-based cermet was sintered by SPS from 1050℃ to 1450℃ and its sintering properties,such as porosity,mechanical properties and phase transformation,were investigated by optical microscopy (OM),scanning electron microscopy (SEM),X-ray diffraction (XRD),and differential scanning calorimeter (DSC).It is found that the spark plasma sintering properties of Ti(C,N)-based cermet differ from those of conventional vacuum sintering.The liquid phase appearance is at least lower by 150℃ than that in vacuum sintering.The porosity decreases sharply below 1 200℃ and reaches minimum at 1 200℃,and afterwards it almost keeps invariable and no longer increases.SPS remarkably accelerates the phase transformation of Ti(C,N)-based cermet and it has a powerful ability to remove oxides in Ti(C,N)-based cermets.Above 1 350℃,denitrification occurred.Fresh graphite phase formed above 1 430℃.Both the porosity and graphite are responsible for the poor TRS.
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.
