[The spectral line profile with different electric microfield distribution functions].

According to Stark broadening theory, Stark broadening spectral line profile is asymmetric in essence considering plasma ions impact. The electric microfield distribution function is very important for the spectral line profile. The Stark broadening spectral line profile is described with different electric microfield distribution functions. The results show that the Stark broadening spectral line profile is similar with the Holtsmark distribution and nearest-neighbor field distribution, and it is diversification with Mayer model. With the decrease in the electrons impact broadening parameter, the influence of different electric microfield distribution functions is diminished. With the decrease in the plasma ions impact parameter, the influence of different electric microfield distribution functions is trailing off. The results also show that the action of electric microfield distribution functions is similar when the plasma ions impact parameter is very small. It is illustrated that the intense impact of plasma ions has great influence on the spectral line profile. The results may have important reference for the plasma diagnosis.

[The Stark broadening and Stark shift with different electric microfield distribution functions].

The Stark broadening and Stark shift were described with different electric microfield distribution functions. These microfield distribution functions include Holtsmark, Neutral Point, Nearest-Neighbor and Mayer model microfield distribution function. The Stark profiles with four microfield distribution functions were studied and the Stark broadening and Stark shift were obtained from the Stark profiles to study the influence of different electric microfield distribution functions on Stark broadening and Stark shift. The results show that the influence of different electric microfield distribution functions on Stark broadening and Stark shift increases with the plasma ions impact parameter with the same electrons impact broadening parameter. With the increase in the plasma electrons impact parameter the influence of different electric microfield distribution functions increases with the same ion impact broadening parameter. Especially, the influence of Mayer model electric microfield distribution function is very distinct when the ion impact broadening parameter is larger. It is illuminated that the plasma ions intense impact has great influence on the spectral line profile. It is very important for the plasma diagnosis to select appropriate electric microfield distribution function. The results have important reference for the plasma diagnosis.

[Measurement of molecular vibrational temperature in dielectric barrier discharge in argon/air at atmospheric pressure].

Vibrational temperature of N2 (C 3IIu) molecules in dielectric barrier discharge (DBD) in argon/air at atmospheric pressure, in which the water electrodes were employed, was measured by using a method of spectrum diagnosis. Emission spectral lines of the N2 second positive band system(C 3IIu --> B 3IIg) and the sequences of vibrational bands with deltav = -1, deltav = -2 and deltav = -3 were used in the calculation. The experiment results show that the molecular vibrational temperature of N2 is in the range from 1 938 K to 2 720 K, and it increases almost linearly with increasing the air content in gas mixture. These results are of great importance to the study of plasma dynamics of DBD.

[Electron excitation temperature of hexagon pattern in argon discharge at atmospheric pressure].

The emission spectrum and the discharge current waveform of argon dielectric barrier discharge at atmospheric pressure were measured when the filaments self-organized in hexagon pattern by using a specially designed experimental setup. Electron excitation temperature of hexagon pattern was calculated using intensity ratio method. It was found that the electron excitation temperature is higher as the frequency of feeding voltage increases. And the temporal correlation among all micro-discharge channels also becomes higher as the frequency of feeding voltage increases. This work gives useful reference for studying pattern formation dynamics.

[Electron excitation temperature of argon dielectric barrier discharge at atmospheric pressure].

The electron excitation temperature was measured by the intensity ratio of two spectral lines in argon dielectric barrier discharge (DBD) at atmospheric pressure. The spectral range is from 690 to 800 nm. It is shown that all of the spectral lines are attributed to neutral Ar atoms. The spectral line 763.51 nm (2P(6)-->1S(5)) and 772.42 nm (2P(2)-->1S(3)) are chosen to estimate the electron excitation temperature. The experimental results show that the electron excitation temperature is in the range of 0.1-0.5 eV. The electron excitation temperature increases with increasing applied voltage, but decreases with increasing gas flow rate. The electron excitation temperature in flowing Ar gas discharge is much different from that in static Ar gas discharge. The result is of great importance to industrial application of DBD.

[Spectrum of dielectric barrier discharge at atmospheric pressure intensified by mixing a little argon].

In this paper, the spectrum of dielectric barrier discharge at atmospheric pressure was measured by using the special setup with two water electrodes. The variation of spectrum was studied when a little argon was mixed. Nitrogen molecular spectrum (C3 IIu(v' = 0 ) --> B3 IIg(v" = 0-4)) and nitrogen atomic spectrum(4d(4) D7/2 --> 3p(4)P1/2(0)) were found in the range of 300-800nm. After a little argon was mixed, the breakdown voltage of discharge obviously decreased. The spectral line intensities of nitrogen molecules and nitrogen atoms increased. The full width at half maximum (FWHM) of spectral line was obviously broadened. Because Stark broadening is a linear function of electron density, it can be seen that electron density increased after a little argon was mixed with the air, which caused the probability of excitation collision of N2 and N with electrons to increase, and the number of N2 and N excited to higher excitation state to increase. So the intensity of spectrum was intensified.