Plasma Sci. Technol.
Citation Search Quick Search
About
   » About Journalnew
   » Editorial Board
   » SCI IF
   » Staff
   » Contact
Browse
   » Accepts
   » In Press
   » Current Issue
   » Earlier Issues
   » View by Fields
   » Top Downloaded
   » Sci Top Cited
Authors
   » Submit an Article
   » Manuscript Tracking
   » Call for Papers
   » Scope
   » Instruction for Authors
   » Copyright Agreement
   » Templates
   » Author FAQs
Referees
   » Thanks to Referees
   » Review Policy
   » Referee Login
   » Referee FAQs
   » Editor in Chief Login
   » Editor Login
   » Office Login
Links
   » CNKI
   » IOPscience
   » ASIPP
   » Editage
   » Enago

ISSN 1009-0630 (Print)
CN 34-1187/TL
HighLights More»   
Current Issue Earlier Issues Accepts In Press Top Downloaded
  Plasma Sci. Technol.--2019, 21 (5)   Published: 03 April 2019
Select | Export to EndNote
Research Note

Discharge characteristics of different lightning air terminals under composite voltages

Chijie ZHUANG (庄池杰) 1, Zezhong WANG (王泽众) 2, Rong ZENG (曾嵘) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 051001 ;  doi: 10.1088/2058-6272/aafdfa
Full Text: PDF (686KB) ( 117 )
Show Abstract ( 8 )

Different types of lightning air terminals have been designed over the years. Concern regarding the effect of different types of air terminals, especially the early streamer emission (ESE)-type, remains controversial. This paper describes the discharge characteristics of different types of air terminals, two of which are quite similar to the ESE-type dynasphere, and concludes that the tested non-standard air terminals have discharge characteristics similar to those of Franklin rods and that their lightning protection performance should be similar.

The 22nd meeting of Chinese electrostatics

Characteristics of DBD micro-discharge at different pressure and its effect on the performance of oxygen plasma reactor

Rui LIU (刘蕊) 1, Zhe YU (俞哲) 1, Huijuan CAO (曹慧娟) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 054001 ;  doi: 10.1088/2058-6272/aafbbc
Full Text: PDF (2015KB) ( 92 )
Show Abstract ( 9 )

The oxygen plasma reactor based on dielectric barrier discharge principle can produce a high concentration of reactive oxygen species, which can cooperate with hydraulic cavitation gas–liquid mixer to realize the application of advanced oxidation technology in water treatment. In this technology, the work pressure of the oxygen plasma reactor is decreased by the vacuum suction effect generated in the snap-back section of the gas–liquid mixed container. In this paper, the characteristics of single micro-discharge at different pressures were investigated with the methods of discharge image, electrical characteristics and spectral diagnosis, in order to analyze the electrical characteristics and reactive oxygen species generation efficiency of oxygen plasma reactor at the pressure range from 60 kPa to 100 kPa. The study indicated that, when the pressure decreases, the duty ratio of ionization in the discharge gap and number of electrons with high energy increases, leading to a rise in reactive oxygen species production. When the oxygen reaches the maximum ionization, the concentration of reactive oxygen species is the highest. Then, the discharge intensity continues to increase, producing more heat, which will decompose the ozone and lower the production of reactive oxygen species. The oxygen plasma reactor has an optimum working pressure at different input powers, which makes the oxygen plasma reactor the most efficient in generating reactive oxygen species.

Effects of temperature on creepage discharge characteristics in oil-impregnated pressboard insulation under combined AC–DC voltage

Fubao JIN (金福宝) 1, Yuanxiang ZHOU (周远翔) 2, Bin LIANG (梁斌) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 054002 ;  doi: 10.1088/2058-6272/aaff01
Full Text: PDF (1314KB) ( 61 )
Show Abstract ( 10 )

Due to the complexity of the valve side winding voltage of the converter transformer, the insulation characteristics of the oil-impregnated pressboard (OIP) of the converter transformer are different from those of the traditional AC transformer. The study on effect of temperature on the creeping discharge characteristics of OIP under combined AC–DC voltage is seriously inadequate. Therefore, this paper investigates the characteristics of OIP creepage discharge under combined AC–DC voltage and discusses the influence of temperature on creepage discharge characteristics under different temperatures from 70°C to 110 °C. The experimental results show that the partial discharge inception voltage and flashover voltage decrease with increasing temperature. The times of low amplitude discharge (LAD) decrease and amplitude of LAD increases. Simultaneously, the times of high amplitude discharge (HAD) gradually increase at each stage of creepage discharge with higher temperature. The analysis indicates that the charge carriers easily accumulate and quickly migrate directional movement along the electric field ahead of discharging. The residual charge carriers are more easily dissipated after discharging. The ‘hump’ region of LAD moves to the direction of higher discharge magnitude. The interval time between two continuous discharges is shortened obviously. The concentration of HAD accelerates the development of OIP insulation creepage discharge. The temperature had an accelerating effect on the development of discharge in the OIP under applying voltage.

Effect of UV radiation aging on creepage discharge characteristics of high temperature vulcanized silicon rubber at high altitude

Fubao JIN (金福宝) 1, Yuanxiang ZHOU (周远翔) 2, Bin LIANG (梁斌) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 054003 ;  doi: 10.1088/2058-6272/aaff0c
Full Text: PDF (2060KB) ( 60 )
Show Abstract ( 9 )

The physicochemical properties and creepage discharge characteristics of aged high temperature Vulcanized (HTV) silicone rubber materials were investigated by ultraviolet radiation (UV) aging method in this study. The experimental results show that as the aging time increases, the creepage discharge flashover voltage increases first and then decreases. But the aging time has little effect on the creepage discharge inception voltage. With the aging time prolonged, the discharge endurance time of HTV silicone rubber is shortened, and the creepage discharge development velocity is accelerated. In the short time of applying voltage to aging material, the magnitude of discharge increases rapidly. According to the partial discharge characteristic parameters of creepage discharge, the whole creepage discharge process is partitioned into four stages. Compared with unaged HTV silicone rubber, the aged HTV silicone rubber has less fluctuation in performance parameters and a clear trend. The study found that UV aging not only affects the physicochemical and hydrophobic properties of the HTV silicone rubber, but also accelerates the development of creepage discharge under AC voltage.

Research on resonance parameters matching based on partitioned operation method of atmospheric pressure plasma reactor array

Zhe YU (俞哲) 1, Jialin ZHAO (赵嘉琳) 1, Rui LIU (刘蕊) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 054004 ;  doi: 10.1088/2058-6272/aaffa2
Full Text: PDF (1813KB) ( 75 )
Show Abstract ( 7 )

Matching optimization of resonant parameters among the high power inverters, low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation method. In this paper, the Matlab/ Simulink electrical model was established based on the method of partitioned operation. The matching relation between resonant parameters is analyzed on the basis of experimental result. As a consequence, transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system, leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters.

Design and characteristics investigation of a miniature low-temperature plasma spark discharge device Hot!

Xue LI (李雪) 1, Renwu ZHOU (周仁武) 2,3, Bo ZHANG (张波) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 054005 ;  doi: 10.1088/2058-6272/aaf111
Full Text: PDF (2227KB) ( 89 )
Show Abstract ( 13 )

Atmospheric pressure low-temperature plasma is a promising tool in biomedicine applications including blood coagulation, bacterial inactivation, sterilization, and cancer treatment, due to its high chemical activity and limited thermal damage. It is of great importance to develop portable plasma sources that are safe to human touch and suitable for outdoor and household operation. In this work, a portable and rechargeable low-temperature plasma spark discharge device (130 mm × 80 mm × 35 mm, 300 g) was designed. The discharge frequency and plume length were optimized by the selection of resistance, capacitance, electrode gap, and ground electrode aperture. Results show that the spark plasma plume is generated with a length of 12 mm and a frequency of 10 Hz at a capacitance of 0.33 μF, resistance of 1 MΩ, electrode gap of 2 mm, and ground electrode aperture of 1.5 mm. Biological tests indicate that the plasma produced by this device contains abundant reactive species, which can be applied in plasma biomedicine, including daily sterilization and wound healing.

Classification and uniformity optimization of mesh-plate DBD and its application in polypropylene modification

Yan HUI (辉妍), Na LU (鲁娜), Pengzhen LUO (罗朋振), et al.
Plasma Sci. Technol. 2019, 21 (5): 054006 ;  doi: 10.1088/2058-6272/aafae1
Full Text: PDF (2760KB) ( 68 )
Show Abstract ( 8 )

The classification of spatial characteristics and discharge modes of dielectric barrier discharge (DBD) are gaining increasing attention in industrial applications, especially in the field of surface treatment of materials. In this work, gray level histogram (GLH) and Fourier energy spectrum based on the digital image processing technology are applied to investigate the spatial structure and discharge mode of mesh-plate DBD. The coefficient of variation (CV) is calculated to describe the uniformity of the discharge. The results show that the discharge mode of mesh-plate DBD changes from periodic discharge to filamentary discharge when the applied voltage increases from 11–15 kV. Moreover, a more regular spatial structure is obtained under lower applied voltages during the discharge process. It is also found that the apertures of mesh electrodes which are below 1mm have smaller values of CV compared to plate electrodes, indicating more uniform discharge. Finally, polypropylene is treated by mesh-plate DBD for surface modification. The hydrophilicity is significantly improved as the water contact angle decreased by 64°, and the dyeing depth is also enhanced.

Effect of power parameters on micro-discharge induced by corona discharge

Yinxia GUAN (关银霞) 1,2, Shiqiang WANG (王世强) 1,2, Shiya TANG (唐诗雅) 1,2, et al.
Plasma Sci. Technol. 2019, 21 (5): 054007 ;  doi: 10.1088/2058-6272/ab0336
Full Text: PDF (1617KB) ( 67 )
Show Abstract ( 6 )

This research mainly describes the generation and diagnosis of plasma using a wire-plate discharge device driven by different power supplies, aimed at investigating the effect of driving source parameters on micro-discharge induced by a corona. The influence of parameters such as waveform, duty ratio and bias voltage on discharge characteristics was explored preliminarily. Experiment results show that the determination of volt-ampere characteristics under different driving source waveforms indicates that the application of square and pulse waveforms shows great advantages over that of sawtooth and sinusoidal waveforms. Similarly, the photo-thermal effects of the system were investigated by comparing the high-voltage electrode temperature and relative emission intensity of N2 (C3Пu →B3Пg , 0–0, 337 nm), where square and pulse waveforms also achieved better performance. But the pulse waveform had a slight advantage over the square waveform in terms of energy conversion. Further, investigations of the duty ratio and bias voltage applied on the pulse waveform were conducted, and the results indicate that the duty ratio could effectively improve the discharge power and thermal effect to a certain extent; however, the application of bias voltage on the pulse signal had little influence on the discharge power and thermal effect.

Study on purification technology of polyacrylamide wastewater by non-thermal plasma

Junfeng RONG (荣俊锋), Kaixun ZHU (朱凯勋) and Minggong CHEN (陈明功)
Plasma Sci. Technol. 2019, 21 (5): 054008 ;  doi: 10.1088/2058-6272/aafceb
Full Text: PDF (1229KB) ( 58 )
Show Abstract ( 9 )

In this work, non-thermal plasma has been applied to treat polyacrylamide (PAM) wastewater. We have investigated the influence 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 1.0 gl −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. The 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 gl −1, pH 1.5. This research provides some basic data and new theoretical basis for PAM wastewater purification.

Magnetically Confined Plasma

Influence of stationary driven helical current on the m=2/n=1 resistive tearing mode

Yun YUAN (袁赟) 1,2, Xingqiang LU (路兴强) 1, Jiaqi DONG (董家齐) 3, et al.
Plasma Sci. Technol. 2019, 21 (5): 055101 ;  doi: 10.1088/2058-6272/aafdc7
Full Text: PDF (1372KB) ( 29 )
Show Abstract ( 9 )

The influence of stationary driven helical current on tearing mode instability in the m=2/n=1 rational surface is explored numerically using resistive magnetohydrodynamic simulation in cylindrical geometry. The results indicate that the flip instabilities result from the sustained injection of the sufficiently strong helical current driven in the island O-point. The driven helical current induces high order harmonics of instabilities due to the delay of suppressing timing and the increase of its current intensity. With the appropriate current density values, the development of the perturbed kinetic energy can be limited and the occurrence of the flip instabilities can be delayed for a long time. The radial deviation of the current deposition can lead to poor inhibition effect, and the effect of current bias on the boundary is greater than that on the axis.

Numerical study of equilibrium solutions for axisymmetric plasmas with toroidal flow obtained using Solovev approach

Yemin HU (胡业民) 1,2, M S ZHU (朱名盛) 1,2 and Wenfeng GUO (郭文峰) 1,2, et al.
Plasma Sci. Technol. 2019, 21 (5): 055102 ;  doi: 10.1088/2058-6272/ab004a
Full Text: PDF (10751KB) ( 33 )
Show Abstract ( 7 )

Solovev approach of finding equilibrium solutions, which was extended to include the vacuum solutions provided by Zheng, Wooton, and Solano, was found extremely useful for the purpose of shaping studies. Its extension to toroidal equilibria with a general plasma flow was examined theoretically in a companion paper by Chu, Hu and Guo. The only meaningful extension was found for plasmas with a pure toroidal rotation and with a constant Mach number. A set of functions {SOLOVEV_ZWSm} was obtained which fixed location of the magnetic axis for equilibria with quasi-constant current density profile, with toroidal flow at constant Mach number and with specific heat capacity 1. The set {Solovev_ZWSm} should have complete shaping capability for plasma shapes with positive curvature at the boundary; but not for plasmas with negative curvature boundary points, i.e. the doublets or bean shaped tokamaks. We report here extensive numerical studies showing the shaping capability of {Solovev_ZWSm} for plasmas with pure toroidal rotations, including the change in topology of the solution when the rotation mach number changes. Included plasma topology are the sphere (spheromaks); and the tokamaks (including the doublets).

Astrophysics and Space Plasma

Effects of electron trapping on nonlinear electron-acoustic waves excited by an electron beam via particle-in-cell simulations

A A ABID 1,4, Quanming LU (陆全明) 1,4, Huayue CHEN (陈华岳) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 055301 ;  doi: 10.1088/2058-6272/ab033f
Full Text: PDF (2044KB) ( 26 )
Show Abstract ( 4 )

By performing one-dimensional particle-in-cell simulations, the nonlinear effects of electron- acoustic (EA) waves are investigated in a multispecies plasma, whose constituents are hot electrons, cold electrons, and beam electrons with immobile neutralized positive ions. Numerical analyses have identified that EA waves with a sufficiently large amplitude tend to trap cold electrons. Because EA waves are dispersive, where the wave modes with different wavenumbers have different phase velocities, the trapping may lead to the mixing of cold electrons. The cold electrons finally get thermalized or heated. The investigation also shows that the excited EA waves give rise to a broad range of wave frequencies, which may be helpful for understanding the broadband-electrostatic-noise spectrum in the Earth’s auroral region.

Low Temperature Plasma

Characteristics of a radio-frequency cold atmospheric plasma jet produced with a hybrid cross-linear-field electrode configuration Hot!

Muhammad Ajmal KHAN, Jing LI (李静), Heping LI (李和平), et al.
Plasma Sci. Technol. 2019, 21 (5): 055401 ;  doi: 10.1088/2058-6272/ab004b
Full Text: PDF (3758KB) ( 33 )
Show Abstract ( 7 )

Cold atmospheric plasma (CAP) jet has wide applications in various fields including advanced materials synthesis and modifications, biomedicine, environmental protection and energy saving, etc. Appropriate control on the volume, temperature and chemically reactive species concentrations of the CAP jet is of great importance in actual applications. In this paper, an radio-frequency atmospheric-pressure glow discharge (RF-APGD) plasma generator with a hybrid cross-linear-field electrode configuration is proposed. The experimental results show that, with the aid of the copper mesh located at the downstream of the traditional co-axial-type plasma generator with a cross-field electrode configuration, a linear field between the inner powered electrode of the traditional plasma generator and the copper mesh can be established. This liner- field can, to some extent, enhance the discharges at the upstream of the copper mesh, resulting in small increments (all less than 12.5%) of the species emission intensities, electron excitation temperatures and gas temperatures by keeping other parameters being unchanged. And due to the intrinsic transparent and conducting features of the grounded copper mesh to the gas flowing, electric current and heat flux of the plasma plumes, a plasma region with higher concentrations of chemically reactive species and larger plasma plume diameters is obtained at the downstream of the grounded copper mesh on the same level of the gas temperature and electron excitation temperature compared to those of the plasma free jet. In addition, the charged particle number densities at the same downstream axial location of the grounded copper mesh decrease significantly compared to those of the plasma free jet. This means that the copper mesh is also, to some extent, helpful for separating the chemically reactive neutral species from the charged particles inside a plasma environment. The preceding results indicate that the cross-linear-field electrode configuration of the plasma generator is an effective approach for tuning the characteristics of the RF-APGD plasma jet in order to obtain an appropriate combination of the plasma jet properties with higher chemically reactive species concentrations, especially relative higher number densities of neutral species, larger plasma volumes and lower gas temperatures.

Study on the discharge mechanism and EM radiation characteristics of Trichel pulse discharge in air

Chuang WANG (王闯), Xi CHEN (陈曦), Kai TANG (唐凯), et al.
Plasma Sci. Technol. 2019, 21 (5): 055402 ;  doi: 10.1088/2058-6272/ab03ab
Full Text: PDF (2019KB) ( 28 )
Show Abstract ( 8 )

The Trichel pulse stage is an unstable stage of negative corona discharge that can also involve electromagnetic (EM) radiation signals. In this paper, the discharge mechanism and radiation characteristics of the Trichel pulse are studied in the needle-plate electrode configuration. The Trichel pulse current and its EM radiation signals are measured at different applied voltages. The results show that Trichel pulse discharge changes from the random pulse stage to the continuous pulse stage as the applied voltage increases. During these different stages, the normalized shape of the Trichel pulses remains unchanged, while the frequency of the EM radiation generated by the discharge remains unchanged. The discharge mechanism and EM radiation characteristics of the Trichel pulse are theoretically analyzed in the different stages. Both the positive ion sheath and the negative ion cloud play key roles in the formation of the Trichel pulse. The EM radiation signal is generated by the rapidly changing Trichel pulse current, and the Trichel pulse current waveform determines the characteristics of the EM radiation signal.

Modeling OH transport phenomena in cold plasma discharges using the level set method

Mehrdad SHAHMOHAMMADI BENI 1, Wei HAN (韩伟) 2,3 and K N YU (余君岳) 1
Plasma Sci. Technol. 2019, 21 (5): 055403 ;  doi: 10.1088/2058-6272/ab008d
Full Text: PDF (2975KB) ( 28 )
Show Abstract ( 7 )

Cold atmospheric plasmas (CAPs) have attracted considerable interest in the field of plasma medicine. Generated reactive species such as hydroxyl (OH) species play an important role in applications of CAPs. Transportation of OH species towards the target and distribution of these OH species in the plasma plume play an important role in the applications of plasma medicine. In the present work, a computational model was built to simulate the transportation and distribution of OH species in CAP discharges, which was based on the level set method to dynamically track the propagation of plasma carrier gas in air. A reaction term was incorporated for the OH species. The OH species tended to diffuse around the main stream of the carrier gas, and thus covered larger radial and axial distances. A CAP discharge onto a skin layer led to the largest accumulation of OH species at the central part of the exposed area. The distribution of OH species on the skin was asymmetric, which agreed with experiments. The computational model itself and the obtained results would be useful for future development of plasma medicine.

Plasma Technology

Surface charge accumulation behavior and its influence on surface flashover performance of Al2O3-filled epoxy resin insulators under DC voltages

Yanqin LIU (刘彦琴) 1, Guangning WU (吴广宁) 1, Guoqiang GAO (高国强) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 055501 ;  doi: 10.1088/2058-6272/aafdf7
Full Text: PDF (1983KB) ( 23 )
Show Abstract ( 6 )

Surface charge accumulation on insulator surface can have great influence on surface flashover performance. An experimental system is established to investigate surface charge accumulation and decay characteristics of Al2O3-filled epoxy resin insulators in 0.1 MPa SF6 under DC voltages. Surface potential is recorded by a Kelvin vibrating probe connected to an electrostatic voltmeter. By pre-depositing charges on insulator surface, the influence of surface charges on surface flashover performance is studied. The results reveal that surface charge distribution appearance is the combined effect of electrode injection, back discharge and gas ionization. Surface charge distribution has obvious polarity effect. It is concentrated near the HV electrode under positive voltages and dispersed under negative voltages. The difference in positive and negative surface flashover voltage is attributed to the difference in surface charge distribution under DC voltages of different polarities. Surface charge decay contains two stages, which satisfies the law of double exponential function. At first stage, surface charge decays fast, which corresponds to charges escaping from shallower traps. While it decays slowly at the second stage, which corresponds to charge escaping from deeper traps. Surface charge decay process is dominated by surface conductivity mechanism. The pre-deposited charges on insulation surface have great influence on surface flashover performance. The deposited positive charges can increase positive flashover voltage but decrease negative flashover voltage.

Super-hydrophobic film deposition by an atmospheric-pressure plasma process and its anti-icing characteristics

Qinghua HUANG (黄清华) 1, Lin XIONG (熊琳) 1, Xiaolong DENG (邓小龙) 2, et al.
Plasma Sci. Technol. 2019, 21 (5): 055502 ;  doi: 10.1088/2058-6272/ab01f4
Full Text: PDF (3460KB) ( 20 )
Show Abstract ( 5 )

In this work, the super-hydrophobic (SH) surface was prepared through chemical vapor deposition process by an argon atmospheric pressure plasma jet source with HMDSN (hexamethyldisilazane) as the polymerization precursor. Plasma synthesized organosilicon (SiOxCyHz) thin films with water contact angle over 160° and sliding angle below 5°, were able to be achieved. FTIR and XPS analysis indicates a large number of hydrocarbon compositions were polymerized in the thin films enduing the latter very-low surface free energy. SEM shows the SH films display micro-nanostructure and with high degree of averaged surface roughness 190 nm evaluated by AFM analysis. From experiments under controlled low-temperature and moisture conditions, the prepared SH surface exhibits good anti-icing effects. Significantly prolonging freezing time was achievable on the SH thin films for both static and sliding water droplets. This investigation demonstrates the anti-icing potentials of SH surface prepared through low-cost simple atmospheric-pressure plasma polymerization process.

Naphthalene oxidation by different non-thermal electrical discharges at atmospheric pressure

M REDOLFI 1, N BLIN-SIMIAND 2, X DUTEN 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 055503 ;  doi: 10.1088/2058-6272/ab01c7
Full Text: PDF (1460KB) ( 14 )
Show Abstract ( 5 )

Gaseous naphthalene has been removed by air plasma generated by pulsed corona discharges at 100°C (LSPM) and dielectric barrier discharges (DBD) up to 250 °C (LPGP) in different reactors geometries. Naphthalene has been chosen as one of unburned hydrocarbon present in exhaust gas engine during the cold start of vehicles. The comparison between the different discharge geometries has been possible using the specific input energy (SIE) as relevant parameter for pollutant removal process control considering the differences in the electrical characteristics and the differences of gas flow. The best naphthalene degradation is obtained in the wire-to cylinder (WTC) corona discharge and the stem-to-cylinder DBD with an energy cost β respectively of 10 and 20 J L -1. The main by-products issues of the naphthalene oxidation are CO2 and CO reaching 45% in Multi-Pin-to-Plan corona discharge. We detected polyaromatic hydrocarbons in the gas phase (few ppm) and in the solid phase deposited in the reactors. The introduction of water in the discharges promotes the naphthalene degradation by OH-atom, which has better oxidising power than O-atom in dry air.

Influence of low-vacuum helium cold plasma pre-treatment on the rooting and root growth of zoysiagrass (Zoysia Willd.) stolon cuttings

Ling LI (李玲) 1, Hailin GUO (郭海林) 1, Junqin ZONG (宗俊勤) 1, et al.
Plasma Sci. Technol. 2019, 21 (5): 055504 ;  doi: 10.1088/2058-6272/aaf368
Full Text: PDF (860KB) ( 21 )
Show Abstract ( 9 )

The influence of low-vacuum helium cold plasma treatment on the rooting percentage, root growth and physiochemical properties of zoysiagrass stolon cuttings was studied. Zoysiagrass stolon cuttings were pre-treated with 0, 100, 200, 300 and 400 W of cold plasma for 15 s. The cold plasma positively stimulated rooting and improved the root growth of the zoysiagrass stolon cuttings, and the 300 W treatment produced the best effect. The rooting percentage and root growth parameters, including the root length, total root surface area, total root volume, average root diameter, and root dry weight, significantly improved in response to the cold plasma treatment. In addition, the water uptake and relative conductivity of the stolon cuttings increased significantly in response to the cold plasma treatment. The results revealed that cold plasma-stimulated rooting and root growth appear to be a consequence of the improvement in permeability and water absorbing capacity of zoysiagrass stolon cuttings. The results of the present study will provide inspiration and support for the application of cold plasma in the vegetative propagation of plants.

The effects of gas flow pattern on the generation of ozone in surface dielectric barrier discharge

Songru XIE (谢松汝), Yong HE (何勇), Dingkun YUAN (袁定琨), et al.
Plasma Sci. Technol. 2019, 21 (5): 055505 ;  doi: 10.1088/2058-6272/aafc50
Full Text: PDF (2257KB) ( 33 )
Show Abstract ( 9 )

Ozone production utilizing surface dielectric barrier discharge (SDBD) was experimental studied for different flow patterns considering the influences of transversal flow, lateral flow and different lateral flow positions. Results show that the flow patterns have a remarkable impact on the ozone yield by affecting the uniformity and turbulence of gas flow. Meanwhile, distributing the O2 flow rate according to the intensity of the plasma reaction would also increase the generation efficiency of SDBD for ozone production. By improving the uniformity and introducing the lateral flow to the transversal flow, the highest ozone yield was obtained in flow pattern ‘F’. In this case, the ozone yield increased by 28.4% to 131 gkWh −1 from 102.8 gkWh−1 in flow pattern ‘A’.

 
News
· The special issue papers from 2018 Asia-Pacific Conference on Plasma and Terahertz Science(APCOPTS) are published on Vol 21 Issue 4 of PST!
·
· PST 2019 Spring Festival Holiday Notice!
· PST Vol 20, Issue 9 published Special Topic-Instabilities and Nonlinear Phenomena in Plasmas-in memory of Prof. Changxuan YU, please feel free to read!
·
· Summer Holiday from 30/07/2018 to 10/08/2018
· PST achieves its highest ever Impact Factor 1.07
· The selected papers from the 1st Asia-Pacific Conference on Plasma Physics are published on Vol 20 Issue 7 of PST!
·
· The selected papers from the 8th International Conference on Applied Electrostatics are published on Vol 20 Issue 5 of PST!
more>>     
Advertisements
Copyright © Plasma Sci. Technol.
Address: Institute of Plasma Physics, Chinese Academy of Sciences, P. O. Box 1126, Hefei 230031, China
Tel: +86-551-65591617  65593176   Fax: +86-551-65591310  E-mail: pst@ipp.ac.cn