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The effects of various remote plasma, such as Ar, He, O2 and N2 on PVC bio-carrier surface modification were studied. The surface properties were characterized by the contact angle measurement and X-ray photoelectron spectroscopy (XPS). The role of all kinds of active species such as electrons, ions and free radicals involved in plasma surface modification were evaluated. Results show that the remote plasma treatments modify the PVC surface in both wettability and composition, the (O + N)/C of PVC surface increases from 7% to 22%, and the water contact angle decreases from 97 degrees to 15 degrees. The optimal results was achieved when plasma treatment parameters were set, that is treatment time 3 min, Ar flux at 20 cm3/s, power at 60W, sample position of 40 cm. The results show that the modified PVC Bio-carrier adhesion rate and capacity on the modified surface are greatly increased.

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.

The soft X-ray and vacuum ultraviolet sources developed in CIOMP are presented. The wall-stabilized argon arc source with spectrum stability and repeatability of +/-0.3% is applied to the calibration of spectrum intensity distribution of the vacuum ultraviolet instruments as an absolute standard source. The Penning source, duobplasma source and hollow cathode source are able to produce atomic and ionic line spectra as a wavelength standard source, which covers a few nanometers to several tens nanometers with spectrum radiation stability and repeatability of +/-1.0%. In particular, the low debris laser produced plasma source with liquid aerosol spray target recently developed can emit stronger soft X-ray for soft X-ray lithography and metrology, which has a transfer efficiency as high as 0.75%/2pi x sr/2% bandwidth.

In this experiment, the effects of gas composition and pressure on the intensity and quality of the plasma induced by a high-energy neodymium glass laser were studied. The experimental results show that the spectral intensity of the plasma in the argon atmosphere is stronger than that in the air when the pressure is the same. For the steel alloy sample, the intensities of the emission spectrum reach the maximum values when the argon pressure is 0.8 x 10(5) Pa. The self-absorption phenomena of Al II 308.22 and Al II 309.27 nm lines strengthen with the increase of the pressure, and even serious self-reversal appears when the pressure is (0.8-0.9) x 10(5) Pa. The temperature of plasma also raises with the increase of the pressure. When the argon pressure is 0.93 x 10(5) Pa, t h e temperature is about 1500 K higher than that when the argon pressure is about 0.43 x 10(5) Pa.

According to mathematic statistics, data for laser microemission spectroscopic analysis were selected, which were collected with the use of CCD (charge-coupled device) in arg on atmosphere at reduced pressure. By selection, the effects of some factors, such as the difference of bore ablated on the sample surface by the laser, the distribution nonuniformity of element in the sample, and the fluctuation of output energy of the laser, etc. were reduced. The method that improves analytic precision of laser microemission spectroscopic analysis was studied. And quantitative analysis of Cu, Zn and Mg in aluminum alloy standard samples was performed, using the Cu (I) line at 324.7 nm, the Zn (I) line at 334.5 nm, and the Mg (I) line at 383.8 nm. The results show that the RSDs of relative intensity of the spectral lines of Cu, Zn, Mg are 1.80%, 4.35% and 6.29% respectively, and the RSDs of quantitative analysis of them are 10.1%, 6.98% and 8.17% respectively. The relative errors of the average of analysis of them are -3.76%, 3.62% and -1.62% respectively.

The nano-graphite powder synthesized by the detonation of explosives with negative oxygen balance is a new powder material with potential applications. In this work, the preparation of nano-graphite powder in steel chamber by pure TNT (trinitrotoluene) explosives has been introduced. In the synthesis process, the protective gases in the steel chamber are N2, CO2 and Ar, and the pressure is 0.25-2 atm. Raman spectrum of the nano-graphite was measured. The characteristic Raman band assigned to sp2 of graphite has been observed at about 1 585 cm(-1) with half-peak width of 22 cm(-1). The peak shifted to a higher frequency by 5 cm(-1) compared with that of bulk graphite. The authors explain this blue shift phenomenon by size effect. The average size of nanographite from Raman measurement is 2.97-3.97 nm. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to measure the structure and particle size of the nano-graphite. The crystallite size of nano-graphite estimated from XRD andTEM are 2.58 nm (acid untreated) and 1.86 nm (acid treated) respectively, which is in accord with the results of the measurement approximately.

Protected with Ar, it would induce atom Ar breakdown to ablate aluminum target with a pulsed Nd: YAG laser beam. Further more, a lot of Ar+ ionic characteristic lines radiation appeared accompanying the aluminum plasma emission. In this work, based on the Ar+ ionic characteristic lines radiation, we analyzed time-resolved behavior of four Ar+ ionic characteristic lines Ar II 385.057, Ar II 386.853, Ar II 404.291 and Ar II 407.201 nm, respectively. Electron temperature of aluminum plasma in the stage of ionic lines emission was approximately calculated. As a result, in this stage, the electron temperature ranged from 15 000 to 22000 K, and decreased successively with the delay time increasing. Compared with other similar works, we found that our results agreed with many similar estimations.

In argon atmosphere at reduced pressure, the spectral analysis reproducibility and sensitivity are experimentally studied with the laser microprobe emission spectral analysis(LMESA) system for the metal alloy standard samples. For the atomic spectral analysis line, the relative standard deviation(RSD) in argon atmosphere at reduced pressure is better than that in air atmosphere. For the ionic spectral analysis line, the RSD is almost the same in both cases. The RSD is strongly affected by the composition of the sample and the concentration of elements. The measured slope of calibration curves for the determination of Cu, Zn and Mg in an aluminum alloy in argon atmosphere is about 1.5-2 times of that in the air atmosphere, which indicates an obvious improvement of the sensitivity and is helpful to expand the dynamic range of the spectral analysis.

An optically thin gaseous mixture of K and low-density Ar is excited by the fixed frequency line 514.5 nm of the argon ion laser. The excited KAr molecule is dissociated into the K 4P1/2 or K 4P3/2. The branching ratio is defined as I(D1)/I(D2) where I(D1) and I(D2) are measured intensities of the atomic K D1 and D2 lines. The branching is determined in the Ar density range between 2 and 8 x 10(17) cm-3. The ratio of the dissociation rates and the fine structure changing cross section are obtained.

For the management of refractory hazardous wastes, an innovative technology emerging recently is the application of ultra high temperature plasma. The preliminary study on destruction of Freon 12 by ICP (1-2kW) under a joint program between Xiamen Univ. and Hong Kong Baptist Univ. showed that the ICP technology indeed holds a great potential for hazardous wastes management. The destruction efficiency is more than 99.9999%. With and without the presence of Freon 12, Ar(I) excitation temperatures were measured by Boltzmann plot method and electron number densities the by H (beta) line broadening method. It was found that above the load coil, the excitation temperatures and electron number densities decrease with increasing the amount of Freon 12 presented in the central channel of the ICP, but inside the load coil region, the excitation temperatures are affected little by Freon 12. The conclusion of thermal pinch could be expected from this phenomenon.