다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Hall-Petch relationship in Mg alloys: A review

Cold atmospheric plasma: Sources, processes, and applications

In this study antimicrobial properties of chitosan and chitosan-zinc oxide (ZnO) nanocomposite coatings on PE films were studied. Oxygen plasma pretreatment of PE films led to increased adhesion by ...

Chitosan-zinc oxide nanoparticle composite coating for active food packaging applications

Pulsed discharge plasma and its application is one of the promising directions in civilian areas of pulsed power technology. In order to promote the research and development of the theory and application technology for pulsed discharge plasma, in this paper, recent progress on the mechanism of nanosecond-pulse gas discharge and the characteristics and applications of typical pulsed plasma at the Institute of Electrical Engineering, Chinese Academy of Sciences is reviewed. Firstly, progress on mechanism of nanosecond-pulse discharge based on runaway electrons and measurement technology of runaway electrons is introduced. Then, the characteristics of three typical discharges, including direct-driven pulsed discharge, pulsed dielectric barrier discharge and pulsed plasma jet, are reviewed. Furthermore, typical plasma applications of pulsed plasma on surface modification and methane conversion are presented.

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/hve.2016.0014

Atmospheric-pressure pulsed discharges and plasmas: mechanism, characteristics and applications

Surface modification of polyimide films using unipolar nanosecond-pulse DBD in atmospheric air

Dielectric barrier discharge excitated by pulsed power is a promising approach for producing nonthermal plasma at atmospheric pressure, but pulsed power generators vary widely in performance and should be chosen according to application requirements. In this paper, a repetitive unipolar nanosecond-pulse generator is constructed using resonant charging and one-stage magnetic compression circuits, where IGBT and magnetic switches are the key units, respectively. The generator is capable of providing repetitive pulses with a voltage of up to 30 kV and duration of 70 ns at a 300 resistive load. Output pulse voltage can be adjusted by varying ac input voltage or trigger pulse-width. This compact and convenient generator has been used successfully to produce stable dielectric barrier discharge.

A Compact Repetitive Unipolar Nanosecond-Pulse Generator for Dielectric Barrier Discharge Application

Atmospheric-pressure gas discharge driven by high voltage pulses with fast rise-time and short duration has attracted significant attention for various plasma applications. In this paper, discharges were generated in a highly non-uniform electric field by point-plane gaps in open air by four repetitive nanosecond-pulse generators with repetition rate up to 1 kHz. The rise time of generators was 25 (generator #1), 15 (generator #2), 3 (generator #3), and 0.2 ns (generator #4) and a full width at half maximum was 40, 30-40, 5, and 1 ns, respectively. The experimental results show that there were typical discharge fashions, i.e., corona, diffuse, spark, or arc modes. The variables affecting the discharge characteristics, including the gap spacing and applied pulse parameters, were investigated. Especially, the diffuse discharges were investigated and discussed. With generator #1 at voltage 70-120 kV, characteristics of measured x-rays on the discharge modes were studied, and it indicates that counts of x-rays in a diffuse discharge are up to a peak value under the experimental conditions. With amplitude of voltage pulses in incident wave up to 18 (generator #3) and 12.5 kV (generator #4), runaway electron beam in low pressure helium, nitrogen, and air in a pulse-periodic mode of discharge with repetition rate up to 1 kHz was obtained. Electron beam was registered behind a thin foil in a pressure range from several to tens of Torr. X-ray radiation was obtained in a wide range of pressures, as well as at atmospheric pressure of helium, nitrogen, and air. Voltage pulses of positive and negative polarities were used. Generation of runaway electrons with pulses of positive polarity appeared because of reflected voltage pulses of reverse polarity.

Diffuse discharge produced by repetitive nanosecond pulses in open air, nitrogen, and helium

Osteogenesis, angiogenesis and immune response of Mg-Al layered double hydroxide coating on pure Mg.

Dielectric barrier discharge (DBD) excitation by unipolar high voltage pulses is a promising approach for producing non-thermal plasma at atmospheric pressure. In this study, a magnetic compression solid-state pulsed power generator was used to produce repetitive nanosecond pulses for the excitation. The DBD is created using two liquid electrodes. The electrical characteristics of the discharge voltage and current are illustrated under different experimental conditions. The nanosecond-pulse discharge current is of the order of tens of amperes. This differs from common DBD current excitated by high-voltage ac sources. Compared with the characteristics of two current pulses corresponding to two discharges for unipolar pulsed-excitation, the secondary discharge in this study is minor owing to the pulsed power and discharge configuration. Under the experimental conditions, the luminous emissions from the front and side views of the liquid electrodes show that no filament is observed and the discharge is homogeneous and diffuse in the whole discharge region. The effects of applied voltage amplitude, repetition rate, and air gap spacing on the discharge characteristic are investigated. The discharge mode does not change with the variation of the investigated parameters. A comparison of high voltage ac and nanosecond-pulse excitation is also presented. In addition, discussion of the experimental results is presented.

Dongdong Zhang

Papers

Surface modification of polyimide films using unipolar nanosecond-pulse DBD in atmospheric air

A Compact Repetitive Unipolar Nanosecond-Pulse Generator for Dielectric Barrier Discharge Application

Diffuse discharge produced by repetitive nanosecond pulses in open air, nitrogen, and helium

Osteogenesis, angiogenesis and immune response of Mg-Al layered double hydroxide coating on pure Mg.

Excitation of atmospheric pressure uniform dielectric barrier discharge using repetitive unipolar nanosecond-pulse generator