The Effect of DBD Plasma Activation Time on the Dyeability of Woven Polyester Fabric with Disperse Dye

This study consists of two parts. In the first, the woven polyester fabric, after washing to remove lubricant oils, was treated with the dielectric barrier discharge (DBD) plasma at the short plasma exposure time (from 15 to 90 s). The effect of the plasma exposure time on the activation of the polyester fabric was assessed by the wicking height of the samples. The results show that the wicking height in the warp direction of the plasma-treated samples improved but was virtually unchanged in the weft direction. Meanwhile, although the tensile strength in the warp direction of the fabric was virtually unaffected despite the plasma treatment time up to 90 s, in the weft direction it increased slightly with the plasma treatment time. Scanning Electron Microscope (SEM) images and the X-ray Photoelectron Spectroscopy (XPS) spectra of the samples before and after the plasma treatment were used to explain the nature of these phenomena. Based on the results of the first part, in the second part, two levels of the plasma treatment time (30 and 60 s) were selected to study their effect on the polyester fabric dyeability with disperse dyes. The color strength (K/S) values of the dyed samples were used to evaluate the dyeability of the fabric. The SEM images of the dyed samples also showed the difference in the dyeability between the plasma-treated and untreated samples. A new feature of this study is the DBD plasma treatment condition for polyester fabrics. The first is the use of DBD plasma in air (no addition of gas). Second is the very short plasma treatment time (only 15 to 90 s); this condition will be very favorable for the deployment on an industrial scale.

Study the Effect of Cold Plasma on the Nonlinear Properties of Polymeric Membranes Rod Amine (R3Go)

The nonlinear optical properties for polymeric (PMMA) doping with dye Rhodmine (R3Go) has been studied .The samples are prepared by normal polymerization method with concentrations of 5x10-5mol/l and a thickness of 272.5µm. Plasma effect was studied on samples prepared before and after exposure to the Nd: YAG laser for three times 5, 10 and 15 minutes. Z-Scan technique is used to determine the nonlinear optical properties such as; refractive index (n2) and the coefficient of nonlinear absorption (β). It was found that the nonlinear properties is change by increasing of plasma exposure time, this result gives good indication about the effect of plasma on the internal structure of the polymer.

Study the Effect of Cold Plasma on the Nonlinear Properties of Polymeric Membranes Rod Amine (R3Go)

The nonlinear optical properties for polymeric (PMMA) doping with dye Rhodmine (R3Go) has been studied .The samples are prepared by normal polymerization method with concentrations of 5x10-5mol/l and a thickness of 272.5µm. Plasma effect was studied on samples prepared before and after exposure to the Nd: YAG laser for three times 5, 10 and 15 minutes. Z-Scan technique is used to determine the nonlinear optical properties such as; refractive index (n2) and the coefficient of nonlinear absorption (β). It was found that the nonlinear properties is change by increasing of plasma exposure time, this result gives good indication about the effect of plasma on the internal structure of the polymer.

Stimulation of wound healing process through ROS/RNS signals indirectly generated by N2/Ar micro-plasma - in vitro and in vivo studies

In this work, non-thermal N2/Ar micro-plasma was applied to fibroblast cells and second degree burn in mice to investigate the bio-safety and bioefficiency of micro-plasma device for studying wound healing process. The chosen parameters of the device were the addition of 0.5% N2 in argon plasma and RF supplied power of 17 W and 13 W in vitro and in vivo studies, respectively. Firstly, micro-plasma was applied to fibroblast cells and the induced biological effect was studied in vitro. The result showed that cells number increased three folds for plasma exposure time of 5 or 10 sec, followed by cell culture for 48 hrs. The cell coverage rate rose 20% for the same plasma exposure time, followed by cell culture for 6 or 12 hrs. Secondly, micro-plasma was applied to the second degree burn wound mice, followed by related ex vivo and in vivo assessments. For the former, 0.5% N2/Ar micro-plasma was competent to generate ROS/RNS signals for advancing healing process by the increase of ROS/RNS concentration around the plasma-exposed wound bed. The induced effect is most probably correlated with the angiogenesis and epithelialization processes of the burn wound on mice.

Pretreatment of the TaSiN Substrate Surface for Copper-MOCVD

Effects of plasma pretreatments to the TaSiN film surface on Cu nucleation were investigated. Scanning electron microscopy (SEM) was used to measure the Cu nucleation density and to observe the morphology of the Cu film. X-ray spectroscopy (XPS) and Auger depth profiling analyses were used to investigate the bonding state of atoms and the concentrations of oxygen and nitrogen at the TaSiN film surface, respectively. Cu nucleation in Cu MOCVD is effectively enhanced by treating the underlying Ta-Si-N film surface with hydrogen plasma prior to Cu MOCVD. The Cu nucleation density in Cu MOCVD increases as the rf-power and the plasma exposure time increase in the hydrogen plasma pretreatment, but it is saturated at the rf-power of 40W and the plasma exposure time of 2min. To increase the rf-power and the plasma exposure time further would increase the plasma radiation damage for the Si substrate. Therefore, 40W and 2min are the optimal process conditions for the hydrogen pretreatment. Copper nucleation is enhanced by hydrogen plasma pretreatment because the plasma treatment removes the nitrogen and oxygen atoms from the Ta-Si-N film surface. Since Ta-Si is a substrate more favorable for Cu nucleation than Ta-Si-N(O), Cu nucleation on the Ta-Si-N film is enhanced by hydrogen plasma pretreatment of the Ta-Si-N film surface.

Investigation of N2 Plasma Effects on the Density Profile of Hydrogen Silsesquioxane Thin Films

ABSTRACTThe density depth profile and chemical bond structure of hydrogen silsesquioxane (HSQ) thin films treated with an N2 plasma with varying power and exposure time were measured using specular x-ray reflectivity (SXR) and Fourier transform infrared (FTIR) spectroscopy. The SXR data indicate that the density profile of an untreated HSQ film is not uniform and four layers with different electron densities were required to fit the SXR data. For HSQ films treated with either increasing plasma power or plasma exposure time, the film roughness increased and a densified layer was observed at the film/air interface. The thickness of the densified layer increased with both plasma power and plasma exposure time. As a result, up to seven distinct layers were used to model the experimental SXR data from plasma treated films. The FTIR data show that the plasma transforms the Si-H bonds in the HSQ film into Si-O bonds leaving more oxygen atoms around a Si atom. These data are also consistent with the densification observed in the SXR measurements. In general, the HSQ film is more sensitive to increasing plasma power than to increasing plasma exposure time.