In this study, we examined the key particles and chemical reactions that substantially influence plasma characteristics. In summarizing the chemical reaction model for the discharge process of N_(2)–O_(2)–H_(2)O(g)m...In this study, we examined the key particles and chemical reactions that substantially influence plasma characteristics. In summarizing the chemical reaction model for the discharge process of N_(2)–O_(2)–H_(2)O(g)mixed gases, 65 particle types and 673 chemical reactions were investigated. On this basis, a global model of atmospheric pressure humid air discharge plasma was developed, with a focus on the variation of charged particles densities and chemical reaction rates with time under the excitation of a 0–200 Td pulsed electric field. Particles with a density greater than 1% of the electron density were classified as key particles. For such particles, the top ranking generation or consumption reactions(i.e. where the sum of their rates was greater than 95% of the total rate of the generation or consumption reactions) were classified as key chemical reactions. On the basis of the key particles and reactions identified, a simplified global model was derived. A comparison of the global model with the simplified global model in terms of the model parameters, particle densities, reaction rates(with time), and calculation efficiencies demonstrated that both models can adequately identify the key particles and chemical reactions reflecting the chemical process of atmospheric pressure discharge plasma in humid air. Thus, by analyzing the key particles and chemical reaction pathways, the charge and substance transfer mechanism of atmospheric pressure pulse discharge plasma in humid air was revealed, and the mechanism underlying water vapor molecules’ influence on atmospheric pressure air discharge was elucidated.展开更多
Positive corona burst pulses are an unstable pulse mode.They appear in a small range of the onset stage,and their current pulses result from the collective movement of charged species.This paper focused on the connect...Positive corona burst pulses are an unstable pulse mode.They appear in a small range of the onset stage,and their current pulses result from the collective movement of charged species.This paper focused on the connections between these pulses and the collective movement of charged species.The movement of species is divided into four parts with respect to time:the(1)initial growth of species,(2)formation and development of the streamer region and negative ion sheath,(3)dead time(the time interval between the pulses),and(4)rapid re-growth of species.The movement of the species in the four parts and the correspondence with the current pulse were analyzed.The numerical results indicated the following:the rapid rising of the species matched the rising edge of the pulses,the streamer region,and negative ion sheath appeared in the falling edge of the primary pulse,and the rapid re-growth of species matched the re-ignition of the pulses.The results were in qualitative agreement with deductions and experimental observations in the literature.展开更多
Trace hydrogen sulphide(H_(2)S)could reflect the severity of insulation faults in gas-insulated switchgear(GIS),therefore,accurate and fast detection of low-concentration H_(2)S is important for on-line monitoring,fau...Trace hydrogen sulphide(H_(2)S)could reflect the severity of insulation faults in gas-insulated switchgear(GIS),therefore,accurate and fast detection of low-concentration H_(2)S is important for on-line monitoring,fault diagnosis,and state evaluation in GIS.Ag-Ti_(3)C_(2)T_(x) chemiresistive-type sensors were fabricated via drop-coating with self-reduction synthesised Ag-doped Ti_(3)C_(2)T_(x).The as-prepared sensors exhibited an excel-lent sensitivity and selectivity to H_(2)S with an extremely low detection of limit of 18.57 parts per billion(ppb)at 25℃(room temperature).The response of Ag-Ti_(3)C_(2)T_(x) sensor to 10 parts per million(ppm)H_(2)S was enhanced~12 times than that of the pristine Ti_(3)C_(2)T_(x) sensor.The compositing of Ti_(3)C_(2)T_(x) with Ag nanoparticles(NPs)enabled the fast response/recovery time for H_(2)S detection.Further analysis found that the enhanced H_(2)S sensing performances could be attributed to chemical sensitisation,adsorbed oxygen species regulation and high Brunauer–Emmett–Teller(BET)surface area.This study paves the way for Ag-Ti_(3)C_(2)T_(x) as room-temperature sensing materials to detect low-concentration H_(2)S in GIS.展开更多
Dear Editor,Dynamins and dynamin-related proteins(DRPs)constitute a large superfamily of GTPases throughout animal,plant,and bacteria and play essential roles in core cellular processes(Praefcke and McMahon,2004).Pla...Dear Editor,Dynamins and dynamin-related proteins(DRPs)constitute a large superfamily of GTPases throughout animal,plant,and bacteria and play essential roles in core cellular processes(Praefcke and McMahon,2004).Plant specific dynamin-related subfamilies share essential functions with those in mammalian cell,e.g.clarthrinmediated endocytosis and fission of mitochondria.展开更多
基金supported by National Natural Science Foundation of China(No.51907145)。
文摘In this study, we examined the key particles and chemical reactions that substantially influence plasma characteristics. In summarizing the chemical reaction model for the discharge process of N_(2)–O_(2)–H_(2)O(g)mixed gases, 65 particle types and 673 chemical reactions were investigated. On this basis, a global model of atmospheric pressure humid air discharge plasma was developed, with a focus on the variation of charged particles densities and chemical reaction rates with time under the excitation of a 0–200 Td pulsed electric field. Particles with a density greater than 1% of the electron density were classified as key particles. For such particles, the top ranking generation or consumption reactions(i.e. where the sum of their rates was greater than 95% of the total rate of the generation or consumption reactions) were classified as key chemical reactions. On the basis of the key particles and reactions identified, a simplified global model was derived. A comparison of the global model with the simplified global model in terms of the model parameters, particle densities, reaction rates(with time), and calculation efficiencies demonstrated that both models can adequately identify the key particles and chemical reactions reflecting the chemical process of atmospheric pressure discharge plasma in humid air. Thus, by analyzing the key particles and chemical reaction pathways, the charge and substance transfer mechanism of atmospheric pressure pulse discharge plasma in humid air was revealed, and the mechanism underlying water vapor molecules’ influence on atmospheric pressure air discharge was elucidated.
基金supported by National Natural Science Foundation of China(No.51907145)。
文摘Positive corona burst pulses are an unstable pulse mode.They appear in a small range of the onset stage,and their current pulses result from the collective movement of charged species.This paper focused on the connections between these pulses and the collective movement of charged species.The movement of species is divided into four parts with respect to time:the(1)initial growth of species,(2)formation and development of the streamer region and negative ion sheath,(3)dead time(the time interval between the pulses),and(4)rapid re-growth of species.The movement of the species in the four parts and the correspondence with the current pulse were analyzed.The numerical results indicated the following:the rapid rising of the species matched the rising edge of the pulses,the streamer region,and negative ion sheath appeared in the falling edge of the primary pulse,and the rapid re-growth of species matched the re-ignition of the pulses.The results were in qualitative agreement with deductions and experimental observations in the literature.
基金National Natural Science Foundation of China,Grant/Award Number:51877157Hubei Province Science Fund for Distinguished Young Scholars,Grant/Award Number:2020CFA097。
文摘Trace hydrogen sulphide(H_(2)S)could reflect the severity of insulation faults in gas-insulated switchgear(GIS),therefore,accurate and fast detection of low-concentration H_(2)S is important for on-line monitoring,fault diagnosis,and state evaluation in GIS.Ag-Ti_(3)C_(2)T_(x) chemiresistive-type sensors were fabricated via drop-coating with self-reduction synthesised Ag-doped Ti_(3)C_(2)T_(x).The as-prepared sensors exhibited an excel-lent sensitivity and selectivity to H_(2)S with an extremely low detection of limit of 18.57 parts per billion(ppb)at 25℃(room temperature).The response of Ag-Ti_(3)C_(2)T_(x) sensor to 10 parts per million(ppm)H_(2)S was enhanced~12 times than that of the pristine Ti_(3)C_(2)T_(x) sensor.The compositing of Ti_(3)C_(2)T_(x) with Ag nanoparticles(NPs)enabled the fast response/recovery time for H_(2)S detection.Further analysis found that the enhanced H_(2)S sensing performances could be attributed to chemical sensitisation,adsorbed oxygen species regulation and high Brunauer–Emmett–Teller(BET)surface area.This study paves the way for Ag-Ti_(3)C_(2)T_(x) as room-temperature sensing materials to detect low-concentration H_(2)S in GIS.
文摘Dear Editor,Dynamins and dynamin-related proteins(DRPs)constitute a large superfamily of GTPases throughout animal,plant,and bacteria and play essential roles in core cellular processes(Praefcke and McMahon,2004).Plant specific dynamin-related subfamilies share essential functions with those in mammalian cell,e.g.clarthrinmediated endocytosis and fission of mitochondria.
